Ideas of Quantum Chemistry P33 ppt

... a function of the configuration of the nuclei. Our motivation is as follows: • economy of computation: ab initio calculations of the electronic energy for larger molecules would have been many orders of ... oligopeptide the num- ber of conformations is of the order 36 of 10 20 , and for a hundred amino acids – 35 Wijnand Schepens, PhD thesis, University of Gand, 2000. 36 The...

Ngày tải lên: 06/07/2014, 09:20

... 742 13.11.1PaulihardnessofthevanderWaalssurface 743 13.11.2Quantumchemistryofconfinedspace–thenanovessels 743 13.12Synthonsandsupramolecularchemistry 744 13.12.1Boundornotbound 745 13.12.2 Distinguished role of the ... Inductionenergynon-additivity 735 13.9.5 Additivityofthesecond-orderdispersionenergy 740 13.9.6 Non-additivityofthethird-orderdispersioninteraction 741 ENGINEERING OF INTERM...

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... is mean value of measurements Fig. 1.9. The results of measurements of a quantity A are the eigenvalues of the operator ˆ A: E 1 and E 2 . Postulate V (spin angular momentum) spin Spin of elementary ... systems. 16 1. The Magic of Quantum Mechanics moving along a single coordinate axis x (the mathematical foundations of quantum mechanics are given in Appendix B on p. 895). P...

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... and some of the inequalities they have to fulfil. The the- orem pertains to the basic logic of the measurements and is valid independently of the kind of particles and of the nature of their interaction. ... Copenhagen for quantum mechanics was like Rome for catholics, and Bohr played the role of the president of the Quantum Faith Con- gregation. 52 The picture of the wor...

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... abyss of the sea without a bottom. 22 The presence of the Dirac sea makes the Dirac the- ory, in fact, a theory of an infinite number of particles, whereas formally it was only a theory of a single ... CALCULATION OF THE GROUND STATE OF THE HYDROGEN-LIKE ATOM WITHIN DIRAC THEORY Matrix form of the Dirac equation We will use the Dirac equation (3.59). First, the basis set compos...

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... disposal all the necessary solutions of eq. (5.16). The eigenfunctions of the ˆ H (0) operator appeared as a consequence of using them as the complete set of functions (e.g., in expanding ψ (1) k ). ... ψ k (λ) are analytical functions of λ (p. 205). In this mathematical aspect of the physical problem we may treat λ as a complex number. Then the radius of convergence ρ of the...

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... describe future vibrations of the molecule (changes of R) as well as its rotations (changes of the direction of R). A simple analogy Let us stop for a while to catch the sense of the adiabatic approximation. To ... PES, for the motion of the nuclei, rep- resents one of the most important ideas in chemistry. This concept makes possible contact with what chemists call the spati...

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... has to be convex as a function of the positions of the nuclei. 6. Please choose the wrong answer. As a result of the rotational excitation J → (J +1) of a molecule of length R: a) the angular momentum ... func- tion in the form of a product of an electronic function and a function describing the motion of the nuclei; c) leads to the notion of the potential energy curve for t...

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... bond One of the molecules is a donor, the other is an acceptor of a proton, Fig. 7.10.a. A local minimum of smaller stability appears when one of the water molecules serves as a donor of two protons, ... 7.10.a): • stretchingofthehydrogenbondO–H O(thevibrationoftwowatermolecules treated as entities): 183 cm −1 • bendingofthehydrogenbondO–H Ointheplaneofthefigure:345cm −1 • bendingoft...

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... correlation of motion of some atoms or groups of atoms, i.e. the space correlation (“when this group of atoms is shifted to correlation and auto-correlation the left, then another group is most often ... (1953) 1087. 314 7. Motion of Nuclei (sometimes it takes months on the fastest computers of the world) and calculat- ing statistics of the number of accepted conformations as...

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