Nghiên cứu một số phân tử kim loại chuyển tiếp có chuyển pha spin

I HC QUC GIA H NI TRNG I HC KHOA HC T NHIấN - Nguyn Th Hiờn NGHIấN CU MT S PHN T KIM LOI CHUYN TIP Cể CHUYN PHA SPIN LUN VN THC S KHOA HC H Ni 2015 I HC QUC GIA H NI TRNG I HC KHOA HC T NHIấN - Nguyn Th Hiờn NGHIấN CU MT S PHN T KIM LOI CHUYN TIP Cể CHUYN PHA SPIN Chuyờn ngnh: Vt lý Nhit Mó s: o to thớ im LUN VN THC S KHOA HC NGI HNG DN KHOA HC: PGS.TS Nguyn Anh Tun H Ni 2015 LI CM N Li u tiờn, tụi xin by t lũng bit n sõu sc nht n thy giỏo, PGS TS Nguyn Anh Tun, ngi ó tn tỡnh hng dn, ng viờn v giỳp tụi sut quỏ trỡnh hon thnh bn lun ny Tụi cng xin gi li cm n chõn thnh nht n cỏc thy cụ giỏo b mụn Vt lý Nhit thp, Khoa Vt lý v cỏc thy cụ giỏo trng i hc Khoa hc T nhiờn ó cung cp cho tụi tht nhiu kin thc b ớch Cui cựng, tụi xin gi li cm n ti Ths Nguyn Vn Thnh v cỏc bn, nhng ngi luụn luụn ng viờn v giỳp tụi sut quỏ trỡnh va qua H Ni, ngy 11 thỏng 11 nm 2015 Nguyn Th Hiờn CC Kí HIU V T VIT TT AO: Qu o nguyờn t (Atomic orbital) CF: Crystal Field DFT: Lý thuyt phim hm mt (Density functional theory) E: Tng nng lng Exc: Nng lng tng quan trao i HOMO: Qu o phõn t cao nht b chim (Highest occupied molecular orbital) HS: Spin cao (High spin) K: ng nng LS: Spin thp (Low spin) LUMO: Qu o phõn t thp nht khụng b chim (Lowest unoccupied molecular orbital) m: mụmen t MO: qu o phõn t (Molecular orbital) n: in tớch P: Nng lng kt cp in t S: Tng spin SCO: Chuyn pha spin (Spin-crossover) U: Th nng tng tỏc tnh in Coulomb : Nng lng tỏch mc trng bỏt din (khe nng lng egt2g) : mt phõn b in t MC LC CHNG M U 10 CHNG PHNG PHP NGHIấN CU Error! Bookmark not defined 2.1 Gii thiu v lý thuyt phim hm mt (DFT) Error! Bookmark not defined 2.1.1 Bai toan cua hờ nhiờu hat Error! Bookmark not defined 2.1.2 Y tng ban õu vờ DFT: Thomas-Fermi va cac mụ hi nh liờn quan Error! Bookmark not defined 2.1.3 i nh ly Hohenberg-Kohn th nht Error! Bookmark not defined 2.1.4 Gii thiờu vờ orbital va ham nng lng Kohn-Sham Error! Bookmark not defined 2.2 Phng phỏp tớnh toỏn Error! Bookmark not defined CHNG CU TRC HèNH HC, CU TRC IN T V CC C TRNG CHUYN PHA SPIN CA PHN T FeL2 Error! Bookmark not defined 3.1 Trng thỏi spin thp Error! Bookmark not defined 3.1.1 Cu trỳc hỡnh hc: Error! Bookmark not defined 3.1.2 Cu trỳc iờn t Error! Bookmark not defined 3.2 Trng thỏi spin cao Error! Bookmark not defined 3.2.1 Cu trỳc hỡnh hc Error! Bookmark not defined 3.2.2 Cu trỳc iờn t Error! Bookmark not defined 3.3 Mt s c trng ca chuyn pha spin Error! Bookmark not defined 3.3.1 S thay i cu trỳc Error! Bookmark not defined 3.3.2 S chuyn iờn tớch Error! Bookmark not defined 3.3.3 S bin i nng lng Error! Bookmark not defined KT LUN CHNG Error! Bookmark not defined CHNG 4NH HNG CA DUNG MễI VI CU TRC HèNH HCCU TRC IN T CA PHN T FeL2 Error! Bookmark not defined 4.1 nh hng ca dung mụi ti cu trỳc hỡnh hc Error! Bookmark not defined 4.2 nh hng ca dung mụi ti in tớch nguyờn t (n) Error! Bookmark not defined 4.3 nh hng ca dung mụi ti mụmen t nguyờn t (m) Error! Bookmark not defined 4.4 nh hng ca dung mụi ti khe nng lng HOMO-LUMO Error! Bookmark not defined 4.5 nh hng ca dung mụi ti chờnh lch nng lng gia cỏc trng thỏi spin Error! Bookmark not defined KT LUN CHNG Error! Bookmark not defined KT LUN Error! Bookmark not defined DANH MC BNG BIU Bng 1.1 Tng spin cỏc trng thỏi LS v HS ca cỏc cu hỡnh in t d4-d7 Bng 3.1 : Cỏc di liờn kt Fe L ca phõn t FeL2 trng thỏi LS t thc nghim v tớnh toỏn Error! Bookmark not defined Bng 3.2: Cỏc di liờn kt Fe L ca phõn t FeL2 trng thỏi HS t tớnh toỏn Error! Bookmark not defined Bng 3.3: Giỏ tr mụmen t ca Fe v sỏu phi t xung quanh ca phõn t FeL2 trng thỏi HS Error! Bookmark not defined Bng 3.4: Cỏc di liờn kt Fe L () trng thỏi LS v HS ca FeL2 thu c t kt qu tớnh toỏn v s liu thc nghim [25] Giỏ tr thc nghim c in nghiờng Cỏc giỏ tr trung bỡnh c in m Error! Bookmark not defined Bng 3.5 in tớch ca Fe v cỏc nguyờn t O1N6 trng thỏi LS (nLS) v trng thỏi HS (nHS) ca FeL2 Error! Bookmark not defined Bng 3.6: Cỏc chờnh lch nng lng (eV) gia trng thỏi HS v LS ca phõn t FeL2, bao gm lch v ng nng (K), nng lng tng tỏc tnh in (U), nng lng tng quan trao i (Exc) v tng nng lng (E) Error! Bookmark not defined Bng 4.1.Cỏc di liờn kt Fe L () trng thỏi LS v HS ca phõn t FeL2 cỏc dung mụi khỏc 39 Bng 4.2 in tớch tớnh toỏn [e] ca ion Fe v cỏc ion L trng thỏi LS v HS ca phõn t FeL2trong chõn khụng v cỏc dung mụi khỏc Error! Bookmark not defined Bng 4.3 Nng lng liờn kt (Eb) ca cỏc trng thỏi LS v HS ca phõn t FeL2 cỏc dung mụi .45 DANH MC HèNH V Hỡnh 1.1: Mt s cu trỳc v s tỏch mc 3d Hỡnh 1.2:Hỡnh dng ca cỏc hm súng eg: (a) dx2-y2, (b) dz2 .3 Hỡnh 1.3: Hỡnh dng ca cỏc hm súng t2g: (a) dxy, (b) dyz v (c) dzx Hỡnh 1.4: S ph lp v lai húa mnh ca cỏc qu o eg vi cỏc qu o p tng ng:(a) dx2-y2 vi px v py, (b) dz2 vi pz .3 Hỡnh 1.5: S ph lp v lai húa ca cỏc qu o t2g (dyz) vi qu o py .4 Hỡnh 1.6: S lai húa p d dn n s y v tỏch ca cỏc mc t2g v eg .4 Hỡnh 1.7: S ph thuc ca nng lng ton phn Et, P v vo trng thỏi spin ca cỏc in t [45] Hỡnh 1.8: S sp xp cỏc in t trờn cỏc mc nng lng v trng thỏi spin .6 Hỡnh 1.9: S chuyn trng thỏi spin ca cỏc phõn t SCO: (a) Di tỏc dng ca nhit , (b) Di tỏc dng ca ỏp sut, (c) Di tỏc dng ca ỏnh sỏng Hỡnh 1.10: ng dng lm thit b hin th ca phõn t chuyn pha spin Hỡnh 1.11: th biu din s tr nhit ca phõn t FeL2[24] 10 Hỡnh 3.1: Cu trỳc hỡnh hc ca phõn tFeL2 ú cỏc nguyờn t hydro c b i cho d nhỡn (Fe: mu tớm, N: mu xanh, O: mu , C: mu xỏm) 25 Hỡnh 3.2: Cu trỳc hỡnh hc ca cỏc phi t xớch o dpbo (bờn trỏi) v phi t trc HIm (bờn phi) ca phõn t FeL2 (N: mu xanh, O: mu ; C: mu xỏm; H: mu trng) 26 Hỡnh 3.3: Phn nhõn ca phõn t FeL2 trng thỏi LS di liờn kt tớnh theo n v (Fe: mu tớm, N: mu xanh, O: mu ) 26 Hỡnh 3.4: Mụ t s phõn b ca cỏc in t trờn cac quy ao 3d phõn t FeL2 trng thỏi LS 27 Hỡnh 3.5: Phn nhõn ca phõn t FeL2 trng thỏi HS di liờn kt tớnh theo n v (Fe: mu tớm, N: mu xanh, O: mu ) Error! Bookmark not defined Hỡnh 3.6: Mụ t s phõn b ca cỏc in t trờn cac quy ao 3d phõn t FeL2 trng thỏi HS Error! Bookmark not defined Hỡnh 3.7: Minh s tng di liờn kt gia st v sỏu phi t xung quanh phõn t chuyn t trng thỏi spin thp sang trng thỏi spin cao (cỏc di liờn kt c lit kờ Bng 3.3) 31 Hỡnh 3.8: Bc tranh mt bin dng in t (Deformation electron density) ca phõn t cỏc trng thỏi spin thp (LS) v spin cao (HS) cho thy cú s tỏi phõn b in t phõn t FeL2 chuyn pha gia trng thỏi LS sang HS Vựng nhn thờm in t so vi trng thỏi nguyờn t c biu din bng cỏc ỏm mõy mu xanh, vựng mt i in t so vi trng thỏi nguyờn t c biu din bng cỏc ỏm mõy mu vng vi mt ti b mt l 0,1 e/3 32 Hỡnh 4.1: Cu trỳc hỡnh hc ca phõn t FeL2 ú cỏc nguyờn t hydro c b i cho d nhỡn (Fe: mu tớm, N: mu xanh, O: mu , C: mu xỏm) 38 Hỡnh 4.2 S thay i t i ca cỏc di liờn kt Fe-L vo ca phõn t FeL2 cỏc dung mụi 39 Hỡnh 4.3 nh hng ca cỏc dung mụi ti in tớch ca cỏc nguyờn t Fe v L trng thỏi LS v HS ca nguyờn t FeL2 41 Hỡnh 4.4 nh hng ca cỏc dung mụi ti in tớch chuyn pha spin t trng thỏi LS sang HS ca nguyờn t FeL2 Error! Bookmark not defined Hỡnh 4.5 S ph thuc ca moment t ca nguyờn t Fe phõn t [FeL2] vo trng thỏi HS Error! Bookmark not defined Hỡnh 4.6 S ph thuc ca khe HOMO-LUMO (ELUMOHOMO) trng thỏi LS v HS ca nguyờn t FeL2vo 44 Hỡnh 4.7 nh hng ca dung mụi ti nng lng liờn kt (Eb) trng thỏi LS v HS ca phõn t FeL2 44 Hỡnh 4.8 (a) S ph thuc ca chờnh lch nng lng gia cỏc trng thỏi spin (E = EHS ELS) ca phõn t FeL2 vo ; (b) S ph thuc ca chờnh lch nng lng tnh in (U = UHS ULS) ca phõn t FeL2vo Error! Bookmark not defined CHNG M U Cỏc nguyờn t kim loi chuyn tip 3d cú lp v in t 3d4s, vớ d: Cr (3d44s2), Mn (3d54s2), Fe (3d64s2) v Co (3d74s2) trng thỏi t qu o 3d ca nguyờn t kim loi chuyn tip cú nng lng bng Tuy nhiờn, cỏc nguyờn t kim loi chuyn tip liờn kt vi cỏc nguyờn t phi kim nh O v N to thnh cỏc phc cht kim loi chuyn tip thỡ cỏc trng thỏi 3d b tỏch mc lc y tnh in ca cỏc ion phi kim i vi cỏc in t cỏc qu o 3d l khỏc S tỏch mc ca cỏc trng thỏi 3d ph thuc vo cu hỡnh cỏc ion phi kim xung quanh nguyờn t kim loi chuyn tip, nh c minh trờn Hỡnh 1.1 (a) (b) (c) Hỡnh 1.1: Mt s cu trỳc v s tỏch mc 3d S tỏch mc ca cỏc trng thỏi 3d to lờn mu sc a dng ca cỏc phc cht kim loi chuyn tip Bờn cnh ú s tỏch mc cng l ngun gc ca nhiu tớnh cht v hin tng vt lý thỳ v, in hỡnh l trng hp i vi cỏc phc cht ca kim loi chuyn tip cú cu trỳc bỏt din, ú cu trỳc c bn nht l mt nguyờn t kim TI LIU THAM KHO Ting Anh Born M., Blinder S M (1927), Annalen der physic, Physik, 84, pp.457 Brack M (1985), Semiclassical description of nuclear bulk properties In DensityFunctional Methods in Physics, New York: Plenum, pp 331-379 Cambi L., Szegử L (1931), ĩber die magnetische Susceptibilitọt der komplexen Verbindungen, 64, pp.25912598 Decurtins S., Gutlich P., Kohler C P., Spiering H., Hauser A (1984), Light-induced excited spin state trapping in a transiton-metal complex: The hexa-1propyltetrazole-iron (II) tetrafluoroborate spin-crossover system, Chem Phys Lett, 105, pp 1-4 Delley B (1990) An allelectron numerical method for solving the local density functional for polyatomic molecules, J Chem Phys, 92, pp 508 Dirac P A M (1930) Note on Exchange Phenomena in the Thomas Atom, Proc Cambridge Phil Soc, 26, pp.376-385 Dolg M., Wedig U., Stoll H., Preuss H (1987), Energyadjusted a b i n i t i o pseudopotentials for the first row transition elements J Chem Phys, 86, pp 866 Fermi E (1928a), A statistical method for the determination of some atomic properties and the application of this method to the theory of the periodic system of elements, Rend Z Phys, 48, pp.73-79 Fermi E (1928b), Sulla deduzione statistica di alcune proprieta dell'atomo, Applicazione alia teoria del systema periodico degli elementi, Rend Accad Lincei, 7, pp 342-346 10 Fermi E (1927), Un metodo statistice per la determinazione di alcune proprieta dell'atomo, Rend Accad Lincei, 6, pp 602-607 11 Fiolhais C., Nogueira F., Marques (Eds) M (2003), A Primer in Density Functional Theory, Springer-Verlag Berlin Heidelberg 12 Fock Z V A (1930) Hatree-Fock theory , Phys, 61, pp 126 13 Gaelle D., Marchivie M., Triki S., Pala J S., Sslaỹn J.-Y., Garcớa C J G., Guionneau P (2008),The Key Role of the Intermolecular Interactions in the Presence of Spin Crossover in Neutral [Fe(abpt)2A2] Complexes (A = Terminal Monoanion N Ligand) Inorg Chem, 47, pp 8921 14 Gombas P (1949), Die statistischen Theorie des Atomes und Ihre Anwendungen Wein, Springer-Verlag 15 Goodwin H A., Gỹtlich P (2004), Spin CrossoverAn Overall Perspective, Top Curr Chem, 233, pp 1-47 16 Gross E K U., Dreizler R M (1979), Thomas-Fermi approach to diatomic systems I Solution of the Thomas-Fermi and Thomas-Fermi-Dirac-Weizsọcker equations Phys Rev A, 20, pp 1798-1807 17 Hartree D R (1928), The Wave Mechanics of an Atom with a non-Coulomb Central Field Proc Camb Phil Soc, 24, pp.328 18 Hohenberg P., Kohn W (1964), Inhomogeneous Electron Gas Phys Rev, 136, pp 864-871 19 Kepenekian M., Guenic B L., Robert V (2009), Primary Role of the Electrostatic Contributions in a Rational Growth of Hysteresis Loop in Spin-Crossover Fe(II) Complexes J Am Chem Soc, 131, pp 11498 20 Klamt A., Schỹỹrmann G (1993), "COSMO: A new approach to dielectric screening in solvents with explicit expressions for the screening energy and its gradient", J Chem Soc., Perkin Trans, 2, pp.79 21 Kohn W., Sham L J (1965),Self-Consistent Equations Including Exchange and Correlation Effects Phys Rev, 140, pp 1133-1138 22 Konigsbruggen P J van., Maeda Y, Oshio H (2004), Spin Crossover in Transition Metal Compounds I, Top Curr Chem, 233, pp 259 23 Levy M., Perdew J P., Sahni V (1984), Exact differential equation for the density and ionization energy of a many-particle system Phys Rev A, 30, pp 2745-2748 24 Lieb E H (1981), Thomas-fermi and related theories of atoms and molecules Rev Mod Phys, 53, pp 603-641 25 Li Z., Guan-Cheng X., Hong-Bin X., Teng Z., Zhe-Ming W., Mei Y and Song G (2010), Microwave-assisted synthesis of silver indium tungsten oxide mesocrystals and their selective photocatalytic propertiesChem Commun., 46, pp 25542556 26 McGarvey J J., Lawthers I (1982), Photochemically-induced perturbation of the A5T equilibrium in Fe11 complexes by pulsed laser irradiation in the metal-to- ligand charge-transfer absorption band, J Chem Soc., Chem Commun, 16, pp 906-907 27 Moliner N., Muủoz M C., Lộtard S., Lộtard J.-F., Solans X., Burriel R., Castro M., Kahn O., Real J A (1999), Inorganica Chimica Acta, 291, pp 279 28 Mulliken R S (1955), Electronic Population Analysis on LCAOMO Molecular Wave Functions I J Chem Phys, 23, pp 1833 29 Parr R G., Yang W (1989), Density-Functional Theory of Atoms and Molecules, Oxford University Press, Oxford 30 Paulsen H.; J Wolny A., Trautwein A X (2005), DFT calculations as a tool to analyse quadrupole splittings of spin crossover Fe(II) complexes Monatshefte fỹr Chemie, 136, pp 11071118 31 Paulsen H., Trautwein A X (2004), Calculation of the electronic energy differences of spin crossover complexesJ Phys Chem Sol, 65, pp 793798 32 Perdew J P., Burke K., Ernzerhof M (1996), Generalized Gradient Approximation Made Simple , Phys Rev Lett, 77, pp 3865 33 Pople J A (1999), Quantum chemical models ,Rev Mod Phys, 71, pp 1267 34 Roos B O., Taylor P R.(1980), Density-Functional Methods for Excited States , Chem Phys, 48, pp.157 35 Roothaan C C J (1951), New Developments in Molecular Orbital Theory , Rev Mod Phys, 23, pp 69-89 36 Springborg M (1997), Density-Functional Methods in Chemistry and Materials Science, JOHN WILEY & SONS 37 Szabo A., Ostlund N S (1996), Introduction to Advanced Electronic Structure Theory ,Modern Quantum Chemistry, Dover 38 Thomas L H (1975), The calculation of atomic fields, Proc Camb Phil Soc, 23, pp 542-548 39 Tuan N A (2012), Journal of Applied Physics, 111, pp 07D101 40 Turner J W., Schultz F A (2001), Solution characterization of the iron(II) bis(1,4 reaction , Inorg Chem, 40, pp 5296 41 Weber B., KapsE., WeigandJ., CarboneraC., LetardJ.-F., AchterholdK., ParakF.-G., Inorg Chem 47,487 (2008) 42 Weber B (2009), Spin crossover complexes with N4O2 coordination sphereThe influence of covalent linkers on cooperative interactions, Coordination Chemistry Reviews, 253, pp 2432-2449 43 Weizsacker C F (1935), Z Phys, 96, pp 431-458 44 Yang W., Parr R G., Lee C (1986), Phase-space approach to the exchange-energy functional of density-functional theory , Phys Rev A, 34, pp 4586-4590 45 Yonei K (1971), An extended Thosmas-Fermi-Dirac theory for diatomic molecule, J Phys Soc Jpn, 31, pp 882-894 46 Ziese M (2001), Spin Electronics, Springer-Verlag Berlin Heidelberg, pp 89-116 CễNG TRèNH KHOA HC CễNG B Do Viet Thang, Nguyen Van Thanh, Nguyen Thi Hien, Nguyen Huy Sinh, Nguyen Anh Tuan, Ligand-driven Spin-crossover Behavior of FeII Molecules, accepted for publication in Materials Transactions [...]... Susceptibilität der komplexen Verbindungen, 64, pp.2591–2598 4 Decurtins S., Gutlich P., Kohler C P., Spiering H., Hauser A (1984), “Light-induced excited spin state trapping in a transiton-metal complex: The hexa-1propyltetrazole-iron (II) tetrafluoroborate spin- crossover system”, Chem Phys Lett, 105, pp 1-4 5 Delley B (1990) “An all‐electron numerical method for solving the local density functional for... (2008),“The Key Role of the Intermolecular π−π Interactions in the Presence of Spin Crossover in Neutral [Fe(abpt)2A2] Complexes (A = Terminal Monoanion N Ligand)” Inorg Chem, 47, pp 8921 14 Gombas P (1949), “Die statistischen Theorie des Atomes und Ihre Anwendungen Wein”, Springer-Verlag 15 Goodwin H A., Gütlich P (2004), Spin CrossoverAn Overall Perspective”, Top Curr Chem, 233, pp 1-47 16 Gross... Oxford 30 Paulsen H.; J Wolny A., Trautwein A X (2005), “DFT calculations as a tool to analyse quadrupole splittings of spin crossover Fe(II) complexes” Monatshefte für Chemie, 136, pp 1107–1118 31 Paulsen H., Trautwein A X (2004), “Calculation of the electronic energy differences of spin crossover complexes”J Phys Chem Sol, 65, pp 793–798 32 Perdew J P., Burke K., Ernzerhof M (1996), “Generalized Gradient... LetardJ.-F., AchterholdK., ParakF.-G., Inorg Chem 47,487 (2008) 42 Weber B (2009), Spin crossover complexes with N4O2 coordination sphere–The influence of covalent linkers on cooperative interactions”, Coordination Chemistry Reviews, 253, pp 2432-2449 43 Weizsacker C F (1935), Z Phys, 96, pp 431-458 44 Yang W., Parr R G., Lee C (1986), “Phase-space approach to the exchange-energy functional of density-functional... extended Thosmas-Fermi-Dirac theory for diatomic molecule”, J Phys Soc Jpn, 31, pp 882-894 46 Ziese M (2001), Spin Electronics, Springer-Verlag Berlin Heidelberg, pp 89-116 CÔNG TRÌNH KHOA HỌC ĐÃ CÔNG BỐ 1 Do Viet Thang, Nguyen Van Thanh, Nguyen Thi Hien, Nguyen Huy Sinh, Nguyen Anh Tuan, Ligand-driven Spin- crossover Behavior of FeII Molecules, accepted for publication in Materials Transactions ... Perkin Trans, 2, pp.79 21 Kohn W., Sham L J (1965),“Self-Consistent Equations Including Exchange and Correlation Effects” Phys Rev, 140, pp 1133-1138 22 Konigsbruggen P J van., Maeda Y, Oshio H (2004), Spin Crossover in Transition Metal Compounds I”, Top Curr Chem, 233, pp 259 23 Levy M., Perdew J P., Sahni V (1984), “Exact differential equation for the density and ionization energy of a many-particle... (1964), “Inhomogeneous Electron Gas” Phys Rev, 136, pp 864-871 19 Kepenekian M., Guenic B L., Robert V (2009), “Primary Role of the Electrostatic Contributions in a Rational Growth of Hysteresis Loop in Spin- Crossover Fe(II) Complexes” J Am Chem Soc, 131, pp 11498 20 Klamt A., Schüürmann G (1993), "COSMO: A new approach to dielectric screening in solvents with explicit expressions for the screening energy