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537 Α-Rhombohedral Boron 139–140 Β-Effect 371–372 Β-Rhombohedral

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537 Α-Rhombohedral Boron 139–140 Β-Effect 371–372 Β-Rhombohedral 537 Index a – adatom adsorption energy as function of α-rhombohedral boron 139–140 metal position in periodic system β-effect 371–372 284–286 β-rhombohedral boron 140–142 – adsorbate coordination in relation to π-bonding. See heavy main-group atoms adsorbate valence 301–303 multiple bonding – molecular adsorption and CO adsorption π helix. See 310 helix 286–296 π-conjugation in donor-substituted – surface group orbitals 296–301 cyanoethynylethenes 365–366 adsorbate bond activation and formation π-conjugation in tunable – different metal surfaces reactivity 317, bis(gem-diethynylethene) fluorophores 318–321 366, 368, 369 – quantum-chemical view of bond activation σ-hole 525, 526, 528, 531 321–328 2p shell accounts radial nodes lack 2–4 adsorbate coordination in relation to adsorbate – high electronegativity and small size of valence 301–303 2p-elements 4–7 alkali metal clusters 172 – hybridization defects influence on magnetic alkali metal-indium clusters 142–143 resonance parameters 14–15 alloying 303–305 anisotropy of current (induced) density – inert-pair effect and dependence on partial (ACID) 396–403, 404 charge of central atom 7–10 anisotropy of magnetic susceptibility and – multiple-bond paradigm and bond strengths exaltation 387–391 13–14 annulene 390, 395, 401, 402, 409 – stereo-chemically active versus inactive lone aromatic compounds and transition states pairs 10–12 magnetic properties 383–384 310 helix 506 – examples 4n+2 interstitial electron rule and ring-cap – – aromatic transition states 406, 407–411 orbital overlap compatibility 122–125 – – benzene and borazine 397–398 ab initio and density functional theory – – coarctate transition states 411, 413–415 calculations of water dimer 510 – – fullerenes 400–401 actinocene 351 – – homoaromatic molecules 403–405 actinyls 349–350 ––Huckel¨ and Mobius¨ structures 401–403 active spaces 253–255, 265 – – organometallic compounds 404, 406 adaptive natural density partitioning (AdNDP) – – pyridine, phosphabenzene, and 425–426, 429, 433, 438, 439 silabenzene 398–399 adatom adsorption energy dependence on – molecules magnetic properties 386–387 coordinative unsaturation of surface atoms – – anisotropy of magnetic susceptibility and 276–283 exaltation 387–391 The Chemical Bond: Chemical Bonding Across the Periodic Table, First Edition. Edited by Gernot Frenking, Sason Shaik. c 2014 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2014 by Wiley-VCH Verlag GmbH & Co. KGaA. 538 Index aromatic compounds and transition states condensed polyhedral clusters stability magnetic properties (contd.) affecting factors – – chemical shifts in NMR 391–392 – exo-polyhedral interactions 134–135 – – quantum theoretical treatment 392–397 – orbital compatibility 135–136 aromaticity 372–784. See also inorganic configuration interaction ansatz 222 aromatic compounds – density matrices 222–223 – historical review 384–386 – truncation procedure 222 – in group 14 cyclopropenylium cation conjugation homologs 375–376 – correlation with experimental data – in metallabenzenes 376–378 – in 1,3-butadienes, 12.1,3-butadiyne, – in neutral exocyclic substituted polyenes, and enones 361–363 ––π-conjugation in donor-substituted cyclopropenes (HC)2 C=X 374–375 Aromatic Ring-Current Sheildings method cyanoethynylethenes 365–366 (ARCS) 424 ––π-conjugation in tunable aromatic stabilization energies (ASEs) 358, bis(gem-diethynylethene) fluorophores 359 366, 368, 369 atoms in molecules (AIM) 237–238 – – Hammett and Hammett–Brown substituent constants 363–365 Coulomb interaction 523, 524, 526, b 528–530, 533 Ba Ga Sb 470–473 7 4 9 Coulomb repulsion overcoming in transition band structures 449 metal complex 494–495 Becke–Johnson (BJ) damping 489 covalency and actinides 342–347 benzene and borazine 397–398 covalent bonds in polar metallic solids Bloch orbitals 447–449 459–462 block-localized wavefunction (BLW) 515 Cr, Mo, and W containing complexes blueshifting hydrogen bonds 516 2 259–263 bond activation quantum-chemical view crystal orbital Hamilton population (COHP) – (100) surface uniqueness 323–325 455, 468, 470 – molecular π bond activation (particle shape crystal orbital overlap population (COOP) dependence) 321–323 curves 455, 468 – molecular π bond activation 325–328 crystal orbitals 449 bond order overlap population (BOOP) 275 crystal versus electronic structure 466–470 bond orders analysis 235–237 Born–Oppenheimer approximation 524 d Born–von Karman periodic boundary democracy principle 67 conditions 447 density functional theory (DFT) 229–230, Brillouin zone 449 276, 277, 284, 286, 288–289, 302, 306, 307, broken spin symmetry 233–235 322, 326, 446, 447, 455, 461, 463, 464–465, Brønsted–Evans–Polanyi relation 317, 320, 482, 510–511 321, 325, 330, 333 density-matrix renormalization group (DMRG) algorithm 227–228, 240, 241, c 242, 245, 246 capping principle 125–126 density of states (DOS) 461, 463, 471, 472 carbones 73–81 – analysis 453–456 carbonyl complexes 181–187 Dewar–Chatt–Duncanson (DCD) model 176 coarctate transition states 411, 413–415 diabatic states model 66–67 complete-active-space diamagnetism 387 configuration-interaction (CASCI) 227 diatomic molecules bonding analysis 27–29 complete-active-space self-consistent-field Diels–Alder reaction 406, 408, 409 (CASSCF) approach 225–227, 245, 348, difference-density techniques 531–533 349, 351, 352 different metal surfaces reactivity 317, complete-graph tensor-network (CGTN) 318–321 228–229 directional electrostatic bonding 523–524 Index 539 – anisotropic molecular electrostatic potential E2L2 two-center complexes 94–95 distribution around atoms 524–528 –Si2L2 –Pb2L2 (L=NHC) 95–101 – difference-density techniques 531–533 – two-center group 13 and group 15 – directional noncovalent interactions 533 complexes B L and N L 101–110 – electrostatic anisotropy, donor–acceptor 2 2 2 2 electron correlation 254, 266, 480, 482, 486, interactions and polarization 528–530 – purely electrostatic models 530–531 495, 496 directional noncovalent interactions 533 – – effects 224, 225, 227, 239, 240, 242, 245 dispersion correction 486, 488–490, electron-counting rules in cluster bonding 492–493, 495 113–114 dispersion interaction 477–480 –4n+2 interstitial electron rule and ring-cap – examples orbital overlap compatibility 122–125 – – Coulomb repulsion overcoming in – capping principle 125–126 transition metal complex 494–495 – electronic requirement of condensed – – hexamethylethane derivatives 493–494 – – substituted ethenes 492–493 polyhedral boranes and mno rule – London dispersion energy theory 480–485 126–134 – theoretical methods to compute dispersion – electronic structure of elemental boron and energy 485 boron-rich metal borides 139 – – general 486 ––α-rhombohedral boron 139–140 – – supermolecular density functional theory ––β-rhombohedral boron 140–142 488–490 – – alkali metal-indium clusters 142–143 – – supermolecular wave function theory ––Mg B electronic structure 143–144 (WFT) 486–488 ∼5 44 – – symmetry-adapted perturbation theory – factors affecting stability of condensed (SAPT) 490, 491 polyhedral clusters donor–acceptor bonding 175, 176, 188, 190, – – exo-polyhedral interactions 134–135 192, 193, 195, 196, 203, 207, 211 – – orbital compatibility 135–136 donor–acceptor complexes of main-group – hypoelectronic metalloboranes 136–138 elements 71–73 – localized bonding schemes for bonding in –EL single-center 73 2 polyhedral boranes 119–122 ––CL carbones 73–81 2 – Wade’s rules 114–119 – – donor–acceptor bonding in heavier electron density distribution analysis tetrylenes ER2 and tetrylones EL2 (E=Si–Pb) 88–94 513–514 – – isoelectronic group 15 and group 13 electronic localization 456–458, 462–466 + homologues (N )L2 and (BH)L2 electron localization function (ELF) 82–88 456, 514 –E2L2 two-center complexes 94–95 – f block applications 341–342 ––SiL –Pb L (L=NHC) 95–101 2 2 2 2 – magnetic versus metallic behavior in K P – – two-center group 13 and group 15 4 3 462–466 complexes B2L2 and N2L2 101–110 donor-acceptor interactions 28, 36, 37, 38, electrostatic and orbital interactions 40, 41, 44–46. See also dispersion interaction 509–510 double bonding 13, 15, 16 electrostatic anisotropy, donor–acceptor interactions and polarization e 528–530 EL2 single-center 73 elemental boron and boron-rich metal borides –CL carbones 73–81 2 electronic structure 139 – donor–acceptor bonding in heavier – α-rhombohedral boron 139–140 tetrylenes ER2 and tetrylones EL2 (E=Si–Pb) 88–94 – β-rhombohedral boron 140–142 – isoelectronic group 15 and group 13 – alkali metal-indium clusters 142–143 + homologues (N )L2 and (BH)L2 82–88 –Mg∼5B44 electronic structure 143–144 540 Index energy decomposition analysis (EDA) 181, homonuclear diatomic molecules 255–258 182, 185, 188, 191, 193, 194, 197, 202, 207, honorary d-elements 19–20 359–360, 373, 374, 376, 378, 482, 483, 491, Huckel¨ and Mobius¨ structures 401–403 511–512. See also transition metal hybridization defects influence on magnetic compounds chemical bonding resonance parameters 14–15 energy decomposition approach to bonding in hydrogen bonding 501–502 f block compounds 338–339 – fundamental properties 502–504 – towards 32-electron rule 340–341 – in biological molecules 506–507 – U–N and U–O bonding in uranyl(VI) – theoretical descriptions complexes 339–340 ––ab initio and density functional theory entanglement measures for single-and calculations of water dimer 510–511 multireference correlation effects – – electron density distribution analysis 239–242 513–514 ethylene and acetylene complexes 190, – – electrostatic and orbital interactions
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