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Preview Inorganic chemistry by Miessler, Gary L. Fischer, Paul J. Tarr, Donald A (2013) Preview Inorganic chemistry by Miessler, Gary L. Fischer, Paul J. Tarr, Donald A (2013) Preview Inorganic chemistry by Miessler, Gary L. Fischer, Paul J. Tarr, Donald A (2013) Preview Inorganic chemistry by Miessler, Gary L. Fischer, Paul J. Tarr, Donald A (2013) Preview Inorganic chemistry by Miessler, Gary L. Fischer, Paul J. Tarr, Donald A (2013)

Inorganic Chemistry Gary L Miessler Paul J Fischer Donald A Tarr Fifth Edition Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Visit us on the World Wide Web at: www.pearsoned.co.uk © Pearson Education Limited 2014 All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without either the prior written permission of the publisher or a licence permitting restricted copying in the United Kingdom issued by the Copyright Licensing Agency Ltd, Saffron House, 6–10 Kirby Street, London EC1N 8TS All trademarks used herein are the property of their respective owners The use of any trademark in this text does not vest in the author or publisher any trademark ownership rights in such trademarks, nor does the use of such trademarks imply any affiliation with or endorsement of this book by such owners ISBN 10: 1-292-02075-X ISBN 13: 978-1-292-02075-4 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Printed in the United States of America P E A R S O N C U S T O M L I B R A R Y Table of Contents Introduction to Inorganic Chemistry Gary L Miessler/Paul J Fischer/Donald A Tarr Atomic Structure Gary L Miessler/Paul J Fischer/Donald A Tarr Simple Bonding Theory Gary L Miessler/Paul J Fischer/Donald A Tarr 47 Symmetry and Group Theory Gary L Miessler/Paul J Fischer/Donald A Tarr 79 Molecular Orbitals Gary L Miessler/Paul J Fischer/Donald A Tarr 129 Acid–Base and Donor–Acceptor Chemistry Gary L Miessler/Paul J Fischer/Donald A Tarr 187 The Crystalline Solid State Gary L Miessler/Paul J Fischer/Donald A Tarr 237 Chemistry of the Main Group Elements Gary L Miessler/Paul J Fischer/Donald A Tarr 273 Coordination Chemistry I: Structures and Isomers Gary L Miessler/Paul J Fischer/Donald A Tarr 341 10 Coordination Chemistry II: Bonding Gary L Miessler/Paul J Fischer/Donald A Tarr 389 11 Coordination Chemistry III: Electronic Spectra Gary L Miessler/Paul J Fischer/Donald A Tarr 441 12 Coordination Chemistry IV: Reactions and Mechanisms Gary L Miessler/Paul J Fischer/Donald A Tarr 477 13 Organometallic Chemistry Gary L Miessler/Paul J Fischer/Donald A Tarr 517 I 14 Organometallic Reactions and Catalysis II Gary L Miessler/Paul J Fischer/Donald A Tarr 589 Greek Alphabet and Names and Symbols for the Elements Gary L Miessler/Paul J Fischer/Donald A Tarr 629 Appendix: Character Tables Gary L Miessler/Paul J Fischer/Donald A Tarr 633 Electron Configurations of the Elements, Physical Constants, and Conversion Factors Gary L Miessler/Paul J Fischer/Donald A Tarr 645 Appendix: Useful Data Gary L Miessler/Paul J Fischer/Donald A Tarr 649 Index 667 H H H B B H H H Introduction to Inorganic Chemistry What Is Inorganic Chemistry? If organic chemistry is defined as the chemistry of hydrocarbon compounds and their derivatives, inorganic chemistry can be described broadly as the chemistry of “everything else.” This includes all the remaining elements in the periodic table, as well as carbon, which plays a major and growing role in inorganic chemistry The large field of organometallic chemistry bridges both areas by considering compounds containing metal–carbon bonds; it also includes catalysis of many organic reactions Bioinorganic chemistry bridges biochemistry and inorganic chemistry and has an important focus on medical applications Environmental chemistry includes the study of both inorganic and organic compounds In short, the inorganic realm is vast, providing essentially limitless areas for investigation and potential practical applications Contrasts with Organic Chemistry Some comparisons between organic and inorganic compounds are in order In both areas, single, double, and triple covalent bonds are found (Figure 1); for inorganic compounds, these include direct metal—metal bonds and metal—carbon bonds Although the maximum number of bonds between two carbon atoms is three, there are many compounds that contain quadruple bonds between metal atoms In addition to the sigma and pi bonds common in organic chemistry, quadruply bonded metal atoms contain a delta (d) bond (Figure 2); a combination of one sigma bond, two pi bonds, and one delta bond makes up the quadruple bond The delta bond is possible in these cases because the metal atoms have d orbitals to use in bonding, whereas carbon has only s and p orbitals energetically accessible for bonding Compounds with “fivefold” bonds between transition metals have been reported (­Figure 3), accompanied by debate as to whether these bonds merit the designation “quintuple.” In organic compounds, hydrogen is nearly always bonded to a single carbon In inorganic compounds, hydrogen is frequently encountered as a bridging atom between two or more other atoms Bridging hydrogen atoms can also occur in metal cluster compounds, in which hydrogen atoms form bridges across edges or faces of polyhedra of metal atoms Alkyl groups may also act as bridges in inorganic compounds, a function rarely encountered in organic chemistry except in reaction intermediates Examples of terminal and bridging hydrogen atoms and alkyl groups in inorganic compounds are in Figure Some of the most striking differences between the chemistry of carbon and that of many other elements are in coordination number and geometry Although carbon is usually limited to a maximum coordination number of four (a maximum of four atoms bonded From Chapter of Inorganic Chemistry, Fifth Edition Gary L Miessler, Paul J Fischer, Donald A Tarr Copyright © 2014 by Pearson Education, Inc All rights reserved Introduction to Inorganic Chemistry FIGURE 1  Single and Multiple Bonds in Organic and Inorganic Molecules Organic H H Inorganic Organometallic O C CO H C C H F H Hg42+ 3Hg F H OC Mn CH3 OC C O NR2 H H C C H O R2N O H S S S S W W S S S O C S NR2 S S OC Cr O C CH3 C OC6H5 OC C O NR2 Cl H C C H N Cl N Cl Cl Os + s Pi s s p p d d + p Delta + d FIGURE 2  Examples of ­Bonding Interactions i-Pr i-Pr i-Pr Cr i-Pr i-Pr Os I Cl Cl Cl Cl Cl Cl Re Sigma 2- Cl Cl O C O C Cr C 2- Re Cl Cl Cl Cl to carbon, as in CH4), numerous inorganic compounds have central atoms with coordination numbers of five, six, seven, and higher; the most common coordination geometry for transition metals is an octahedral arrangement around a central atom, as shown for [TiF6]3 - (Figure 5) Furthermore, inorganic compounds present coordination geometries different from those found for carbon For example, although 4-coordinate carbon is nearly always tetrahedral, both tetrahedral and square-planar shapes occur for 4-coordinate compounds of both metals and nonmetals When metals are in the center, with anions or neutral molecules (ligands) bonded to them (frequently through N, O, or S), these are called ­coordination complexes; when carbon is the element directly bonded to metal atoms or ions, they are also classified as organometallic complexes i-Pr Cr i-Pr i-Pr H H FIGURE 3  Example of Fivefold Bonding OC H B B H O C CO Cr H OC C O H H3C H H3C O C CO Cr CO OC C O H3 C Al CH3 Al CH3 C H3 Li - Li = CH3 Li Li Each CH3 bridges a face of the Li4 tetrahedron FIGURE 4  Examples of ­Inorganic Compounds ­Containing Terminal and Bridging Hydrogens and ­Alkyl Groups CH3 OC C O Introduction to Inorganic Chemistry F F Ti F F F F 3- 3- F FF F F Ti F Xe F F F F F Xe F FCl H P N FCl N Cl H N Pt H N H H H 22- B B F HH H N B N B B B F B B B B B B B B B F B F F I B N NB B B B N P N B B F F B B HB BF HH B H P H B F H B P H PP P H Cl Pt H P H H F F F I F F 2- (not B12H12one shown: shown: one B12H122- (not hydrogen on eachhydrogen boron) on each boron) FIGURE 5  Examples of ­Geometries of Inorganic ­Compounds + Fe Cr F3C S F3C S Mo Mo S CF3 S CF3 Ni Ni Zn Zn FIGURE 6  Inorganic Compounds Containing Pi-Bonded Aromatic Rings The tetrahedral geometry usually found in 4-coordinate compounds of carbon also occurs in a different form in some inorganic molecules Methane contains four hydrogens in a regular tetrahedron around carbon Elemental phosphorus is tetratomic (P4) and tetrahedral, but with no central atom Other elements can also form molecules in which outer atoms surround a central cavity; an example is boron, which forms numerous structures containing icosahedral B12 units Examples of some of the geometries found for inorganic compounds are in Figure Aromatic rings are common in organic chemistry, and aryl groups can also form sigma bonds to metals However, aromatic rings can also bond to metals in a dramatically different fashion using their pi orbitals, as shown in Figure The result is a metal atom Fe1CO23 bonded above the center of the ring, almost as if suspended in space In many cases, metal atoms are sandwiched between two aromatic rings Multiple-decker sandwiches of metals and aromatic rings are also known 1CO23Fe Fe1CO23 Carbon plays an unusual role in a number of metal cluster compounds in which a C carbon atom is at the center of a polyhedron of metal atoms.1CO2 Examples of carbon-centered Fe1CO23 3Fe clusters with five, six, or more surrounding metals are known (Figure 7) The striking role that carbon plays in these clusters has provided a challenge to theoretical inorganic chemists In addition, since the mid-1980s the chemistry of elemental carbon has flourished This phenomenon began with the discovery of fullerenes, most notably the cluster C60, dubbed “buckminsterfullerene” after the developer of the geodesic dome Many other fullerenes (buckyballs) are now known and serve as cores of a variety of derivatives In Fe1CO23 1CO23Fe Fe1CO23 C 1CO23Fe 1CO23Ru Fe1CO23 OC 1CO22Ru 1CO23Ru Ru1CO22 C 1CO22R Ru1CO23 Ru1CO23 Ru1CO23 FIGURE 7  Carbon-Centered Metal Clusters Introduction to Inorganic Chemistry FIGURE 8  The Fullerene C60, a Fullerene Compound, a Carbon Nanotube, Graphene, a Carbon Peapod, and a Polyyne “Wire” Connecting Platinum Atoms addition, numerous other forms of carbon (for example, carbon nanotubes, nanoribbons, graphene, and carbon wires) have attracted much interest and show potential for applications in fields as diverse as nanoelectronics, body armor, and drug delivery Figure provides examples of these newer forms of carbon The era of sharp dividing lines between subfields in chemistry has long been ­obsolete Many of the subjects in this text, such as acid–base chemistry and organometallic reactions, are of vital interest to organic chemists Other topics such as ­oxidation–reduction reactions, spectra, and solubility relations interest analytical chemists Subjects related to structure determination, spectra, conductivity, and theories of bonding appeal to physical chemists Finally, the use of organometallic catalysts provides a connection to petroleum and polymer chemistry, and coordination compounds such as hemoglobin and ­metal-containing enzymes provide a similar tie to biochemistry Many inorganic chemists work with professionals in other fields to apply chemical discoveries to addressing modern challenges in medicine, energy, the environment, materials science, and other fields In brief, modern inorganic chemistry is not a fragmented field of study, but has numerous interconnections with other fields of science, medicine, technology, and other disciplines The remainder of this chapter is devoted to a short history of the origins of inorganic chemistry and perspective on more recent developments, intended to provide a sense of connection to the past and to place some aspects of inorganic chemistry within the context of larger historical events The History of Inorganic Chemistry Even before alchemy became a subject of study, many chemical reactions were used and their products applied to daily life The first metals used were probably gold and copper, which can be found in the metallic state in nature Copper can also be readily formed by the reduction of malachite—basic copper carbonate, Cu2(CO3)(OH)2—in charcoal fires Silver, tin, antimony, and lead were also known as early as 3000 bce Iron appeared in Introduction to Inorganic Chemistry classical Greece and in other areas around the Mediterranean Sea by 1500 bce At about the same time, colored glasses and ceramic glazes were introduced, largely composed of silicon dioxide (SiO2, the major component of sand) and other metallic oxides, which had been melted and allowed to cool to amorphous solids Alchemists were active in China, Egypt, and other centers of civilization early in the first centuries ce Although much effort went into attempts to “transmute” base metals into gold, alchemists also described many other chemical reactions and operations Distillation, sublimation, crystallization, and other techniques were developed and used in their studies Because of the political and social changes of the time, alchemy shifted into the Arab world and later—about 1000 to 1500 ce—reappeared in Europe Gunpowder was used in Chinese fireworks as early as 1150, and alchemy was also widespread in China and India at that time Alchemists appeared in art, literature, and science until at least 1600, by which time chemistry was beginning to take shape as a science Roger Bacon (1214–1294), recognized as one of the first great experimental scientists, also wrote extensively about alchemy By the seventeenth century, the common strong acids—nitric, sulfuric, and hydrochloric—were known, and systematic descriptions of common salts and their reactions were being accumulated As experimental techniques improved, the quantitative study of chemical reactions and the properties of gases became more common, atomic and molecular weights were determined more accurately, and the groundwork was laid for what later became the periodic table of the elements By 1869, the concepts of atoms and molecules were well established, and it was possible for Mendeleev and Meyer to propose different forms of the periodic table Figure illustrates Mendeleev’s original periodic table.* The chemical industry, which had been in existence since very early times in the form of factories for purifying salts and for smelting and refining metals, expanded as methods for preparing relatively pure materials became common In 1896, Becquerel discovered radioactivity, and another area of study was opened Studies of subatomic particles, spectra, and electricity led to the atomic theory of Bohr in 1913, which was soon modified by the quantum mechanics of Schrödinger and Heisenberg in 1926 and 1927 Inorganic chemistry as a field of study was extremely important during the early years of the exploration and development of mineral resources Qualitative analysis methods were H=1 Li = Be = 9.4 B = 11 C = 12 N = 14 O = 16 F = 19 Na = 23 Mg = 24 Al = 27.4 Si = 28 P = 31 S = 32 Cl = 35.5 K = 39 Ca = 40 ? = 45 ?Er = 56 ?Yt = 60 ?In = 75.6 Ti = 50 V = 51 Cr = 52 Mn = 53 Fe = 56 Ni = Co = 59 Cu = 63.4 Zn = 65.2 ? = 68 ? = 70 As = 75 Se = 79.4 Br = 80 Rb = 85.4 Sr = 87.6 Ce = 92 La = 94 Di = 95 Th = 118 ? Zr = 90 Nb = 94 Mo = 96 Rh = 104.4 Ru = 104.2 Pd = 106.6 Ag = 108 Cd = 112 Ur = 116 Sn = 118 Sb = 122 Te = 128? J = 127 Cs = 133 Ba = 137 ? = 180 Ta = 182 W = 186 Pt = 197.4 Ir = 198 Os = 199 Hg = 200 FIGURE 9  Mendeleev’s 1869 Periodic Table Two years later, Mendeleev revised his table into a form similar to a modern short-form periodic table, with eight groups across Au = 197? Bi = 210? Tl = 204 Pb = 207 *The original table was published in Zeitschrift für Chemie, 1869, 12, 405 It can be found in English translation, together with a page from the German article, at web.lemoyne.edu/~giunta/mendeleev.html See M Laing, J Chem Educ., 2008, 85, 63 for illustrations of Mendeleev’s various versions of the periodic table, including his handwritten draft of the 1869 table Symmetry and Group Theory The vibrational mode of Ag symmetry is not IR active, because it does not have the same symmetry as a Cartesian coordinate x, y, or z (this is the IR-inactive symmetric stretch) The mode of symmetry B3u, on the other hand, is IR active, because it has the same symmetry as x In summary, there are two vibrational modes for C i O stretching, one having the same symmetry as Ag, and one the same symmetry as B3u The Ag mode is IR inactive (it does not have the symmetry of x, y, or z); the B3u mode is IR active (it has the symmetry of x) We therefore expect to see one C i O stretch in the IR It is therefore possible to distinguish cis- and trans@ML2(CO)2 by taking an IR spectrum If one C i O stretching band appears, the molecule is trans; if two bands appear, the molecule is cis A significant distinction can be made by a very simple measurement EXAMPLE Determine the number of IR-active CO stretching modes for fac@Mo(CO)3(CH3CH2CN)3, as shown in the margin This molecule has C3v symmetry The operations to be considered are E, C3, and sv E leaves the three bond vectors unchanged, giving a character of C3 moves all three vectors, giving a character of Each sv plane passes through one of the CO groups, leaving it unchanged, while interchanging the other two The resulting character is The representation to be reduced, therefore, is as follows: E 2C3 3sv O This reduces to A1 + E A1 has the same symmetry as the Cartesian coordinate z and is therefore IR active E has the same symmetry as the x and y coordinates together and is also IR active It represents a degenerate pair of vibrations, which appear as one absorption band, as shown in Figure 28 Infrared absorptions associated with specific bonds are commonly designated as n(XY), where XY is the bond that contributes most significantly to the vibrational modes responsible for the absorptions In Figure 28, the n(CO) spectrum features absorptions at 1920 and 1790 cm−1 RCN C R C C Mo C N N C R O O R = C2H5 EXERCISE 13  Determine the number of IR-active C i O stretching modes for Mn(CO)5Cl E Absorbance A1 1.2 1920.29 1.6 1.4 FIGURE 28  ­Infrared spectrum of fac-Mo(CO)3(CH3CH2CN)3 1790.17 1.8 1.0 0.8 0.6 0.4 0.2 -0.0 2400 2000 1800 2200 Wavenumbers (cm-1) 1600 113 Symmetry and Group Theory Raman Spectroscopy This spectroscopic method uses a different approach to observe molecular vibrations Rather than directly observing absorption of infrared radiation as in IR spectroscopy, in Raman spectroscopy higher energy radiation, ordinarily from a laser, excites molecules to higher electronic states, envisioned as short-lived “virtual” states Scattered radiation from decay of these excited states to the various vibrational states provides information about vibrational energy levels that is complementary to information gained from IR spectroscopy In general, a vibration can give rise to a line in a Raman spectrum if it causes a change in polarizability.* From a symmetry standpoint, vibrational modes are Raman active if they match the symmetries of the functions xy, xz, yz, x2, y2, or z2 or a linear combination of any of these; if vibrations match these functions, they also occur with a change in polarizability These functions are among those commonly listed in character tables In some cases—when molecular vibrations match both these functions and x, y, or z—molecular vibrations can be both IR and Raman active EXAMPLE Vibrational spectroscopy has played a role in supporting the tetrahedral structure of the highly explosive XeO4 Raman spectroscopy has shown two bands in the region expected for Xe i O stretching vibrations, at 776 and 878 cm - 1.1 Is this consistent with the proposed Td structure? To address this question, we need to once again create a representation, this time using the Xe “ O stretches as a basis in the Td point group The resulting representation is ⌫ E 8C3 3C2 6S4 6sd 0 This reduces to A1 + T2: 2- O F F F I F F O A1 1 1 T2 -1 -1 x + y + z2 (x, y, z) (xy, xz yz) Both the A1 and T2 representations match functions necessary for Raman activity The presence of these two bands is consistent with the proposed Td symmetry EXERCISE 14  Vibrational spectroscopy has played a role in supporting the pentagonal bipyramidal structure of the ion IO2F52 - Raman spectroscopy of the tetramethyl­ ammonium salt of this ion shows a single absorption in the region expected for I=O stretching vibrations, at 789 cm - Is a single Raman band consistent with the proposed trans orientation of the oxygen atoms? *For more details, see D J Willock, Molecular Symmetry, John Wiley & Sons, Chichester, UK, 2009, pp. 177–184 114 Symmetry and Group Theory References M Gerken, G J Schrobilgen, Inorg Chem., 2002, 41, 198 J A Boatz, K O Christe, D A Dixon, B A Fir, M. ­Gerken, R Z Gnann, H P A Mercier, G J ­Schrobilgen, Inorg Chem., 2003, 42, 5282 General References There are several helpful books on molecular symmetry and its applications Good examples are D J Willock, Molecular ­Symmetry, John Wiley & Sons, Chichester, UK, 2009; F A Cotton, Chemical Applications of Group Theory, 3rd ed., John Wiley & Sons, New York, 1990; S F A Kettle, Symmetry and ­Structure: Readable Group Theory for Chemists, 2nd ed., John Wiley & Sons, New York, 1995; and I Hargittai and M Hargittai, ­ ymmetry Through the Eyes of a Chemist, 2nd ed., Plenum Press, S New York, 1995 The last two also provide information on space groups used in solid state symmetry, and all give relatively gentle introductions to the mathematics of the subject For an explanation of situations involving complex numbers in character tables, see S F A Kettle, J Chem Educ., 2009, 86, 634 Problems Determine the point groups for a Ethane (staggered conformation) b Ethane (eclipsed conformation) c Chloroethane (staggered conformation) d 1,2-Dichloroethane (staggered anti conformation) Determine the point groups for H H a Ethylene C C b Chloroethylene H H c The possible isomers of dichloroethylene Determine the point groups for a Acetylene b H i C ‚ C i F c H i C ‚ C i CH3 d H i C ‚ C i CH2Cl e H i C ‚ C i Ph (Ph = phenyl) Determine the point groups for a Naphthalene b 1,8-Dichloronaphthalene Cl Cl Determine the point groups for a 1,1Ј - Dichloroferrocene b Dibenzenechromium (eclipsed conformation) Fe Cl Cr c Cr d H3O + e O2F2 f Formaldehyde, H2CO g S8 (puckered ring) c 1,5-Dichloronaphthalene Cl F O F S Cl O S S S S S S S h Borazine (planar) H Cl d 1,2-Dichloronaphthalene Cl H B H N B N B Cl H H N H 115 Symmetry and Group Theory i [Cr(C2O4)3]3 - O O O O O O Cr O O O O O j A tennis ball (ignoring the label, but including the pattern on the surface) Determine the point groups for a Cyclohexane (chair conformation) b Tetrachloroallene Cl2C “ C “ CCl2 c SO42 d A snowflake e Diborane H H H B H H B H f The possible isomers of tribromobenzene g A tetrahedron inscribed in a cube in which alternate corners of the cube are also corners of the tetrahedron h B3H8 H H H B H H B B H H g The meander motif h An open, eight-spoked umbrella with a straight handle i A round toothpick j A tetrahedron with one green face, the others red Determine the point groups for a A triangular prism b A plus sign c A t-shirt with the letter T on the front d Set of three wind turbine blades e A spade design (as on a deck of playing cards) f A sand dollar H i A mountain swallowtail butterfly j The Golden Gate Bridge, in San Francisco, CA Determine the point groups for a A sheet of typing paper b An Erlenmeyer flask (no label) c A screw d The number 96 e Five examples of objects from everyday life; select items from five different point groups f A pair of eyeglasses, assuming lenses of equal strength g A five-pointed star h A fork with no decoration i Wilkins Micawber, David Copperfield character who wore a monocle j A metal washer Determine the point groups for a A flat oval running track b A jack (child's toy) c A person's two hands, palm to palm d A rectangular towel, blue on front, white on back 116 e A hexagonal pencil with a round eraser f The recycle symbol, in three dimensions 3- O 10 11 12 13 g Flying Mercury sculpture, by Giambologna at the ­Louvre in Paris, France h An octahedron with one blue face, the others yellow i A hula hoop j A coiled spring Determine the point groups for the examples of symmetry in Figure This question was intentionally removed from this edition Determine the point groups of the molecules and ions in a Figure b Figure 15 Determine the point groups of the following atomic orbitals, including the signs on the orbital lobes: a px b dxy c dx2 - y2 d dz2 e fxyz Symmetry and Group Theory 14 a. Show that a cube has the same symmetry elements as an octahedron b Suppose a cube has four dots arranged in a square on each face as shown What is the point group? c Suppose that this set of dots is rotated as a set 10° clockwise on each face Now what is the point group? c Honduras d Field of stars in flag of Micronesia 15 Suppose an octahedron can have either yellow or blue faces a What point groups are possible if exactly two faces are blue? b What points are possible if exactly three faces are blue? c Now suppose the faces have four different colors What is the point group if pairs of opposite faces have identical colors? 16 What point groups are represented by the symbols of ­chemical elements? 17 Baseball is a wonderful game, particularly for someone interested in symmetry Where else can one watch a batter step from an on-deck circle of a symmetry to a rectangular batter's box of b symmetry, adjust a cap of c symmetry (it has OO on the front, for the Ozone City Oxygens), swing a bat of d symmetry (ignoring the label and grain of the wood) across a home plate of e symmetry at a baseball that has f symmetry (also ignoring the label) that has been thrown by a chiral pitcher having g symmetry, hit a towering fly ball that bounces off the fence, and race around the bases, only to be called out at home plate by an umpire who may have no appreciation for symmetry at all 18 Determine the point groups for the following flags or parts of flags You will need to look up images of flags not shown a Botswana 19 20 21 b Finland 22 e Central design on the Ethiopian flag: f Turkey g Japan h Switzerland i United Kingdom (be careful!) Prepare a representation flowchart according to the format of Table for SNF3 For trans-1,2-dichloroethylene, which has C2h symmetry, a List all the symmetry operations for this molecule b Write a set of transformation matrices that describe the effect of each symmetry operation in the C2h group on a set of coordinates x, y, z for a point (your answer should consist of four * transformation matrices) c Using the terms along the diagonal, obtain as many irreducible representations as possible from the transformation matrices You should be able to obtain three irreducible representations in this way, but two will be duplicates You may check your results using the C2h character table d Using the C2h character table, verify that the irreducible representations are mutually orthogonal Ethylene has D2h symmetry a List all the symmetry operations of ethylene b Write a transformation matrix for each symmetry operation that describes the effect of that operation on the coordinates of a point x, y, z c Using the characters of your transformation matrices, obtain a reducible representation d Using the diagonal elements of your matrices, obtain three of the D2h irreducible representations e Show that your irreducible representations are mutually orthogonal Using the D2d character table, a Determine the order of the group b Verify that the E irreducible representation is orthogonal to each of the other irreducible representations 117 Symmetry and Group Theory c For each of the irreducible representations, verify that the sum of the squares of the characters equals the order of the group d Reduce the following representations to their component irreducible representations: D2d E 2S4 C2 2C2Ј 2sd ⌫1 2 ⌫2 6 ⌫ 2C3 3sv ⌫2 -1 -1 E 8C3 6C2 6C4 3C2 i 6S4 0 0 2 8S6 3sh 6sd 24 For D4h symmetry use sketches to show that dxy orbitals have B2g symmetry and that dx2 - y2 orbitals have B1g symmetry (Hint: you may find it useful to select a molecule that has D4h symmetry as a reference for the operations of the D4h point group Observe how the signs on the orbital lobes change as the symmetry operations are applied.) 25 Which items in Problems through Problem are ­chiral? List three items not from this chapter that are chiral 26 XeOF4 has one of the more interesting structures among noble gas compounds On the basis of its symmetry, a Obtain a representation based on all the motions of the atoms in XeOF4 b Reduce this representation to its component irreducible representations c Classify these representations, indicating which are for translational, rotational, and vibrational motion d Determine the irreducible representation matching the xenon–oxygen stretching vibration Is this vibration IR active? 27 Repeat the procedure from the previous problem, parts a through c, for the SF6 molecule and determine which vibrational modes are IR active 28 For the following molecules, determine the number of ­IR-active C i O stretching vibrations: a c.  Fe(CO)5 b.  OC C O O C Cl Fe Cl C O Cl CO OC Fe CO C O Cl OC OC CO C O 29 Repeat Problem 28 to determine the number of ­Raman-active C i O stretching vibrations 118 I Si H a What is the point group of this molecule? b Predict the number of IR-active Si i I stretching ­vibrations c Predict the number of Raman-active Si i I stretching vibrations 31 Both cis and trans isomers of IO2F4 - have been observed Can IR spectra distinguish between these? Explain, supporting your answer on the basis of group theory (Reference: K O Christe, R D Wilson, C J Schack, Inorg Chem., 1981, 20, 2104.) 32 White elemental phosphorus consists of tetrahedral P4 molecules and is an important source of phosphorus for synthesis In contrast, tetrahedral As4 (yellow arsenic) is unstable, and decomposes to a grey As allotrope with a sheet structure However, AsP3, previously only observed at high temperature in the gas phase, has been isolated at ambient temperature as a white solid, where an As atom replaces one vertex of the tetrahedron a The Raman spectrum of AsP3, shown next, exhibits four absorptions Is this consistent with the proposed structure? (Facile Synthesis of AsP3, Brandi M Cossairt, MariamCéline Diawara, Christopher C Cummins © 2009 The American Association for the Advancement of Science Reprinted with permission from AAAS.) 557 cm-1 40000 35000 345 cm-1 428 cm-1 30000 25000 20000 15000 10000 5000 313 cm-1 200 300 400 500 600 Raman shift (cm-1) 0 O C Fe Si I Intensity (a.u.) Oh E ⌫1 I H I 23 Reduce the following representations to irreducible representations: C3v 30 The structure of 1,1,2,2-tetraiododisilane is shown here (Reference: T H Johansen, K Hassler, G Tekautz, K Hagen, J Mol Struct., 2001, 598, 171.) 500 1000 1500 2000 2500 3000 3500 Raman shift (cm-1) b If As2P2 is ever isolated as a pure substance, how many Raman absorptions would be expected? (Reference: B.  M.­ Cossairt, C C Cummins, J Am Chem Soc 2009, 131, 15501.) c Could a pure sample of P4 be distinguished from pure AsP3 simply on the basis of the number of Raman absorptions? Explain Symmetry and Group Theory 33 Complexes of the general formula Fe(CO)5 - x(PR3)x are long known The bimetallic Fe2(CO)9 reacts with ­triphenylphosphine in refluxing diethyl ether to afford a monosubstituted product Fe(CO)4(PPh3) that exhibits n (CO) absorptions at 2051, 1978, and 1945 cm -1 in ­hexane (N J Farrer, R McDonald, J S McIndoe, Dalton Trans., 2006, 4570.) Can these data be used to unambiguously establish whether the PPh3 ligand is bound in either an equatorial or axial site in this trigonal bipyramidal complex? Support your decision by determining the number of IR-active CO stretching modes for these isomers 34 Disubstituted Fe(CO)3(PPh3)2 (n(CO): 1883 cm - ; M. O. Albers, N J Coville, T V Ashworth, E J S ­ ingleton, Organomet Chem., 1981, 217, 385.) is also formed in the reaction described in Problem 33 Which of the following molecular geometries is supported by this spectrum? Support your decision by determining the number of IRactive CO stretching modes for these isomers What does R L Keiter, E A Keiter, K H Hecker, C A Boecker, ­Organometallics 1988, 7, 2466 indicate about the infallibility of group theoretical CO stretching mode infrared spectroscopic prediction in the case of Fe(CO)3(PPh3)2? CO OC Fe CO PPh3 PPh3 PPh3 OC Fe PPh3 CO CO PPh3 OC Fe CO PPh3 CO 35 The reaction of [Ti(CO)6]2- and chlorotriphenylmethane, Ph3CCl, results in rapid oxidation of [Ti(CO)6]2- to afford a trityltitanium tetracarbonyl complex (P J Fischer, K A Ahrendt, V G Young, Jr., J E Ellis, Organometallics, 1998, 17, 13) On the basis of the IR spectrum (n(CO)): 1932, 1810 cm-1) acquired in tetrahydrofuran solution, shown next, is this complex expected to exhibit a square planar or a square pyramidal arrangement of four CO ligands bound to titanium? Does the spectrum rule out either of these possible geometries? cis/trans isomerization does not occur Instead a new complex (n(CO) (hexane): 2085, 2000 (very weak), 1972, 1967 cm-1) is formed (D J Darensbourg, T. L Brown, Inorg Chem 1968, 7, 959.) Propose the formula of this Mo carbonyl complex consistent with the n(CO) IR spectra data Support your answer by determining its expected number of CO stretching modes for comparison with the published spectrum 37 Three isomers of W2Cl4(NHEt)2(PMe3)2 have been reported These isomers have the core structures shown here Determine the point group of each (Reference: F A Cotton, E V Dikarev, W-Y Wong, Inorg Chem., 1997, 36, 2670.) Cl P Cl N W Cl P W Cl P W P W Cl N Cl P Cl W N N W N C P Cl Cl Cl III II I 38 Derivatives of methane can be obtained by replacing one or more hydrogen atoms with other atoms, such as F, Cl, or Br Suppose you had a supply of methane and the necessary chemicals and equipment to make derivatives of methane containing all possible combinations of the elements H, F, Cl, and Br What would be the point groups of the molecules you could make? There are many possible molecules, and they can be arranged into five sets for assignment of point groups 39 Determine the point groups of the following molecules: a F3SCCF3, with a triple S i C bond F F S F C F F F C b C6H6F2Cl2Br2, a derivative of cyclohexane, in a chair conformation Br 0.8 Absorbance Cl N F 0.6 F Cl Cl Br c M2Cl6Br4, where M is a metal atom 0.4 Br 0.2 Cl 0.0 2000 1900 1800 Wavenumbers 1700 1600 36 A related reaction to the one described in Problem  34, in which cis - Mo(CO)4(POPh3)2 rearranges to trans@Mo(CO)4(POPh3)2, has been probed mechanistically (D J Darensbourg, J R Andretta, S M Stranahan, J H Reibenspies, Organometallics 2007, 26, 6832.) When this reaction is conducted under an atmosphere of carbon monoxide, Cl M Br Cl Cl Br M Cl Cl Br d M(NH2C2H4PH2)3, considering the NH2C2H4PH2 rings as ­planar N P N M P N P e PCl2F3 (the most likely isomer) 119 Symmetry and Group Theory 40 Assign the point groups of the four possible structures for asymmetric bidentate ligands bridging two metals in a “paddlewheel” arrangement: (Reference: Y Ke, D J ­Collins, H Zhou, Inorg Chem 2005, 44, 4154.) B A A M A B M B A B A A M B A B M B A A M B A B M A B B Re OC C O A M B A A M B A 41 Determine the point groups of the following: a The cluster anion [Re3(m3 - S)(m - S)3Br9]2 ­(Reference: H. Sakamoto, Y Watanabe, T Sato, Inorg Chem., 2006, 45, 4578.) Br8 Br9 Br7 L L C Re Cl L L O L C O Re CO L Corner 1L = N N2 d The [Bi7I24]3 - ion (Reference: K.Y Monakhov, C ­Gourlaouen, R Pattacini, P Braunstein, Inorg Chem., 2012, 51, 1562 This reference also has alternative depictions of this structure S4 I I I Br2 I I Br4 Ge132 Ge142 Ge122 Ge152 Ge112 Fe112 Ge182 Ge192 Ge172 120 Ge1102 Ge162 I I Bi I I I I I I Bi I I I Bi I Bi b The cluster anion [Fe@Ga10]3− (Reference: B Zhou, M S Denning, D L Kays, J M Goicoechea, J Am Chem Soc., 2009, 131, 2802) I Bi I Bi 3- I Bi Br6 Br3 C C O I S1 O L Br1 Re2 Re Square S3 Br5 OC Cl I Re1 Cl Cl Re3 S2 O C O C Re CO Cl OC B O C O C B B A c The “corner” and “square” structures: (Reference: W H Otto, M H Keefe, K E Splan, J T Hupp, C K Larive, Inorg Chem 2002, 41, 6172.) I I 42 Use the Internet to search for molecules with the symmetry of a The Ih point group b The T point group c The Ih point group d The Th point group Report the molecules, the URL of the Web site where you found them, and the search strategy you used Symmetry and Group Theory Answers to Exercises S2 is made up of C2 followed by s#, which is shown in the figure below to be the same as i z (x, y, z) y x C2 (-x, -y, z) s› (-x, -y, -z) i S1 is made up of C1 followed by s#, which is shown in the figure below to be the same as s z (x, y, z) (x, y, z) y x C1 s› (x, y, -z) s NH3 has a threefold axis through the N perpendicular to the plane of the three hydrogen atoms and three mirror planes, each including the N and one H 2C3, 3sv N H H C3 H Cyclohexane in the boat conformation has a C2 axis perpendicular to the plane of the lower four carbon atoms and two mirror planes that include this axis and are perpendicular to each other C2, 2sv Cyclohexane in the chair conformation has a C3 axis perpendicular to the average plane of the ring, three perpendicular C2 axes passing between carbon atoms, and three mirror planes passing through opposite carbon atoms and perpendicular to the average plane of the ring It also contains a center of inversion and an S6 axis collinear with the C3 axis A model is very useful in analysis of this molecule 2C3, 3C2, 3sd, i, 2S6 XeF2 is a linear molecule, with a Cϱ axis through the three nuclei, an infinite number of perpendicular C2 axes, a horizontal mirror plane (which is also an inversion center), and an infinite number of mirror planes that include the Cϱ axis Cϱ , ϱ C2, i = sh, ϱ sv Several of the molecules below have symmetry elements in addition to those used to assign the point group N2F2 has a mirror plane through all the atoms, which is the sh plane, perpendicular to the C2 axis through the N “ N bond There are no other symmetry elements, so it is C2h B(OH)3 also has a sh mirror plane, the plane of the molecule, perpendicular to the C3 axis through the B atom Again, there are no others, so it is C3h C2 C3 F Xe F 121 Symmetry and Group Theory 122 H2O has a C2 axis in the plane of the drawing, through the O atom and between the two H atoms It also has two mirror planes, one in the plane of the drawing and the other perpendicular to it; overall, C2v PCl3 has a C3 axis through the P atom and equidistant from the three Cl atoms Like NH3, it also has three sv planes, each through the P atom and one of the Cl atoms; overall, C3v BrF5 has one C4 axis through the Br atom and the F atom in the plane of the drawing, two sv planes (each through the Br atom, the F atom in the plane of the drawing, and two of the other F atoms), and two sd planes between the equatorial F atoms; overall, C4v HF, CO, and HCN all are linear, with the infinite rotation axis through the center of all the atoms There are also an infinite number of sv planes, all of which contain the Cϱ axis; overall, Cϱv N2H4 has a C2 axis perpendicular to the N i N bond and splitting the angle between the two lone pairs There are no other symmetry elements, so it is C2 P(C6H5)3 has only a C3 axis, much like that in NH3 or B(OH)3 The twist of the phenyl rings prevents any other symmetry; C3 BF3 has a C3 axis perpendicular to the sh plane of the molecule and three C2 axes, each through the B atom and an F atom; overall, D3h PtCl4 - has a C4 axis perpendicular to the sh plane of the molecule It also has four C2 axes in the plane of the molecule, two through opposite Cl atoms and two splitting the Cl i Pt i Cl angles, thus making it D4h Os(C5H5)2 has a C5 axis through the center of the two cyclopentadienyl rings and the Os, five C2 axes parallel to the rings and through the Os atom, and a sh plane parallel to the rings through the Os atom, for a D5h assignment Benzene has a C6 axis perpendicular to the sh plane of the ring and six C2 axes in the plane of the ring, three through two C atoms each and three between the atoms These are sufficient to make it D6h F2, N2, and H i C ‚ C i H are all linear, each with a Cϱ axis through the atoms There are also an infinite number of C2 axes perpendicular to the Cϱ axes and a sh plane perpendicular to the Cϱ axes, sufficient to make them D ϱ h Allene, H2C “ C “ CH2, has a C2 axis through the three carbon atoms and two C2 axes perpendicular to the line of the carbon atoms, both at 45° angles to the planes of the H atoms Two sd mirror planes through each H i C i H combination complete the assignment of D2d Ni(C4H4)2 has a C4 axis through the centers of the C4H4 rings and the Ni, four C2 axes perpendicular to the C4 through the Ni, and four sd planes, each including two opposite carbon atoms of the same ring and the Ni; overall, D4d Fe(C5H5)2 has a C5 axis through the centers of the rings and the Fe, five C2 axes perpendicular to the carbon atoms and through the Fe, and five sd planes that include the C5 axis; overall, D5d [Ru(en)3] has a C3 axis perpendicular to the drawing through the Ru and three C2 axes in the plane of the paper, each intersecting an en ring at the midpoint and passing through the Ru; overall, D3 2+ Symmetry and Group Theory 1 a C 2 S * C S 3 (5 * 2) + (1 * 1) + (3 * 5) (5 * 1) + (1 * 2) + (3 * 4) (5 * 1) + (1 * 3) + (3 * 3) = C (4 * 2) + (2 * 1) + (2 * 5) (4 * 1) + (2 * 2) + (2 * 4) (4 * 1) + (2 * 3) + (2 * 3) S (1 * 2) + (2 * 1) + (3 * 5) (1 * 1) + (2 * 2) + (3 * 4) (1 * 1) + (2 * 3) + (3 * 3) 26 19 17 = C 20 16 16 S 19 17 16 b C -1 -2 (1 * 2) - (1 * 1) - (2 * 3) -5 -1 S * C S = C (0 * 2) + (1 * 1) - (1 * 3) S = C -2 S (1 * 2) + (0 * 1) + (0 * 3) c [1 3] * C -1 -2 -1 S = [(1 * 1) + (2 * 2) + (3 * 3) = [14 - 1] C0 0 0 S = transformation matrix for E x x 0S CyS = CyS z z or xЈ x C yЈ S = C y S zЈ z sv Ј(yz): Reflect a point with coordinates (x, y, z) through the yz plane xЈ = new x = - x yЈ = new y = y zЈ = new z = z In matrix notation, xЈ C yЈ S = C zЈ * ( - 2) + * ( - 1) + (3 * 1)] E: The new coordinates are xЈ = new x = x yЈ = new y = y zЈ = new z = z * ( - 1) + (2 * 1) + (3 * 2) -1 C 0 0 S = transformation matrix for sv Ј (yz) In matrix notation, xЈ -1 C yЈ S = C zЈ 0 0 x -x 0S CyS = C yS z z or xЈ -x C yЈ S = C y S zЈ z 123 F1 andy Group Theory Symmetry N N x Representation Flow Chart: N2F2 (CF2h) Symmetry Operations F1 y F1 N Symmetry Operations N F2 N x F2 N F2 N N N h 0FS -1 0 C2: C -1 [1] 124 0S -1 sh: C 0 0 0S -1 –1 –3 0 S [1] C [ -1] 0 [ -1] 0 S [1] C [ -1] 0 [ - 1] 0 S [ - 1] [1] C 0 [1] 0 S [ - 1] Coordinate Used E C2 i sh –1 –1 x –1 –1 y (x and y give the same irreducible representation) 1 –1 –1 –1 –3 z Chiral molecules may have only proper rotations The C1, Cn, and Dn groups—along with the rare T, O, and I groups—meet this condition 0 -1 0 0 sxz: I 0 0 0 0 0 O -1 O -1 i: C 0 Irreducible Representations ⌫ x 0S Block Diagonalized Matrices [1] C 0 N after sh Characters of Matrix Representations N N F2 after i O N F1 after C2 1N 0N E: C 0after 0s F1 O N F1 F1 after i y F1 Matrix Representations (Reducible) N F1 after C2 N after E F2 N N F2 F2 ations F2 0 0 0 0 0 0 0 0 -1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -1 0 -1 0 0 0 Y syz: I 0 0 0 0 0 0 0 0 0 0 0 0 0 -1 0 0 0 0 0 0 0 0 0 -1 0 0 0 0 The reducible representation (D2h symmetry) is: D2h E C2(z) C2(y) C2(x) i s(xy) s(xz) s(yz) ⌫ 18 0 –2 0 0 0 0 0 0 0Y 0 Symmetry and Group Theory This reduces to: Ag + B1g + B2g + B3g + Au + B1u + B2u + B3u Translational modes (matching x, y, and z): B1u + B2u + B3u Rotational modes (matching R x, Ry, and Rz): B1g + B2g + B3g Vibrational modes (all that remain): Ag + B1g + B2g + Au + B1u + B2u + B3u 10 a ⌫1 = A1 + T2: For A1: For A2: For E: For T1: For T2: 24 24 24 24 24 Td E 8C3 3C2 6S4 6sd ⌫1 0 A1 1 1 A2 1 –1 –1 E –1 0 T1 –1 –1 T2 –1 –1 * [(4 * 1) + 8(1 * 1) + 3(0 * 1) + 6(0 * 1) + 6(2 * 1)] = * [(4 * 1) + 8(1 * 1) + 3(0 * 1) + 6(0 * ( - 1)) + 6(2 * ( - 1))] = * [(4 * 2) + 8(1 * ( - 1)) + 3(0 * 2) + 6(0 * 0) + 6(2 * 0)] = * [(4 * 3) + 8(1 * 0) + 3(0 * ( - 1)) + 6(0 * 1) + 6(2 * ( - 1))] = * [(4 * 3) + 8(1 * 0) + 3(0 * ( - 1)) + 6(0 * ( - 1)) + 6(2 * 1)] = Adding the characters of A1 and T2 for each operation confirms the result b ⌫2 = A1 + B1 + E: For A1: For A2: For B1: For B2: For E: 8 8 D2d E 2S4 C2 2C2 Ј 2sd ⌫2 0 A1 1 1 A2 1 –1 –1 B1 –1 1 –1 B2 –1 –1 E –2 0 * [(4 * 1) + 2(0 * 1) + (0 * 1) + 2(2 * 1) + 2(0 * 1)] = * [(4 * 1) + 2(0 * 1) + (0 * 1) + 2(2 * ( - 1)) + 2(0 * ( - 1))] = * [(4 * 1) + 2(0 * ( - 1)) + (0 * 1) + 2(2 * 1) + 2(0 * ( - 1))] = * [(4 * 1) + 2(0 * ( - 1)) + (0 * 1) + 2(2 * ( - 1)) + 2(0 * 1)] = * [(4 * 2) + 2(0 * 0) + (0 * ( - 2)) + 2(2 * 0) + 2(0 * 0)] = Adding the characters of A1, B1, and E for each operation confirms the result c ⌫3 = A2 + B1 + B2 + 2E: C4v E 2C4 C2 2sv 2sd ⌫3 –1 –1 –1 –1 A1 1 1 A2 1 –1 –1 B1 –1 1 –1 B2 –1 –1 E –2 0 125 Symmetry and Group Theory For A1: For A2: For B1: For B2: For E: 126 * [(7 * 1) + 2(( - 1) * 1) + (( - 1) * 1) + 2(( - 1) * 1) + 2(( - 1) * 1)] = * [(7 * 1) + 2(( - 1) * 1) + (( - 1) * 1) + 2(( - 1) * ( - 1)) + 2(( - 1) * ( - 1))] = * [(7 * 1) + 2(( - 1) * ( - 1)) + (( - 1) * 1) + 2(( - 1) * 1) + 2(( - 1) * ( - 1))] = * [(7 * 1) + 2(( - 1) * ( - 1)) + (( - 1) * 1) + 2(( - 1) * ( - 1)) + 2(( - 1) * 1)] = * [(7 * 2) + 2(( - 1) * 0) + (( - 1) * ( - 2)) + 2(( - 1) * 0) + 2(( - 1) * 0)] = 11 The A2u (matching symmetry of z) and both Eu (matching symmetry of x and y together) vibrational modes are IR active 12 Vibrational analysis for NH3: C3v E 2C3 3sv ⌫3 12 A1 1 A2 1 –1 E –1 z Rz (x, y) (Rx, Ry) a A1: 16[(12 * 1) + 2(0 * 1) + 3(2 * 1)] = A2: 16[(12 * 1) + 2(0 * 1) + 3(2 * ( - 1))] = E: ⌫ = 3A1 + A2 + 4E b Translation: A1 + E, based on the x, y, and z entries in the table Rotation: A2 + E, based on the R x, Ry, and Rz entries in the table Vibration: 2A1 + 2E remaining from the total; the A1 vibrations are symmetric stretch and symmetric bend The E vibrations are asymmetric c There are three translational modes, three rotational modes, and six vibrational modes, for a total of 12 With atoms in the molecule, 3N = 12, so there are 3N degrees of freedom in the ammonia molecule d All the vibrational modes are IR active (all have x, y, or z symmetry) 13 Taking only the C i O stretching modes for Mn(CO)5 Cl (only the vectors between the C and O atoms): Cl OC C O 8 8 CO Mn CO C O [(12 * 2) + 2(0 * ( - 1)) + 3(2 * 0)] = C4v E 2C4 C2 2sv 2sd ⌫ 1 A1 1 1 z A2 1 –1 –1 Rz B1 –1 1 –1 B2 –1 –1 E –2 0 (x, y) (Rx, Ry) ⌫ = 2A1 + B1 + E Mn(CO)5Cl should have four IR-active stretching modes, two from A1 and two from E The E modes are a degenerate pair; they give rise to a single infrared band The B1 mode is IR inactive 14 Using as basis the I “ O bonds, the following representation is obtained in the D5h point group: D5h E 2C5 2C5 5C2 sh 2S5 2S5 5sv ⌫ 2 0 0 Symmetry and Group Theory This reduces to: A1 Ј 1 1 1 1 x + y 2, z A2 Љ 1 –1 –1 –1 –1 z The A1 Ј vibration matches the symmetry of x2 + y2 and z2; it is Raman active The A2 Љ does not match xy, xz, yz, or a squared term; it matches z and is therefore active in the IR but not in the Raman spectrum Therefore, the single Raman band is consistent with trans orientation 127 ... Inorganic Chemistry Gary L Miessler /Paul J Fischer /Donald A Tarr Atomic Structure Gary L Miessler /Paul J Fischer /Donald A Tarr Simple Bonding Theory Gary L Miessler /Paul J Fischer /Donald A Tarr... Symmetry and Group Theory Gary L Miessler /Paul J Fischer /Donald A Tarr 79 Molecular Orbitals Gary L Miessler /Paul J Fischer /Donald A Tarr 129 Acid–Base and Donor–Acceptor Chemistry Gary L Miessler /Paul. .. Spectra Gary L Miessler /Paul J Fischer /Donald A Tarr 441 12 Coordination Chemistry IV: Reactions and Mechanisms Gary L Miessler /Paul J Fischer /Donald A Tarr 477 13 Organometallic Chemistry Gary

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