Matches in SemOpenAlex for { <https://semopenalex.org/work/W2030781154> ?p ?o ?g. }
Showing items 1 to 95 of
95
with 100 items per page.
- W2030781154 endingPage "4504" @default.
- W2030781154 startingPage "4494" @default.
- W2030781154 abstract "Accurate SCF—LCAO—MO wavefunctions have been computed for acetylene neutral ground state, singly excited π→π* states, and for the acetylene anion and cation. A limited basis set of Slater orbitals was used, the carbon 2s, 2pπ, and 2pσ orbital exponents were independently optimized for each state, and hydrogen 1s for the ground state. All integrals were computed accurately. For the ground state the C2p±1 optimized orbital (ξ=1.59) is very different from the C2pσ optimized orbital (ξ=2.03) with the result that the Π cloud does not penetrate the Σ cloud as greatly as would be predicted by Slater or best-atom AO. However, the penetration remains sizeable (Fig. 2). The ground-state energy − 76.678 a.u. (1 a.u.=27.2098 eV) is improved by 0.134 a.u. over McLean's best-atom calculations, but is 0.176 a.u. poorer than McLean's Hartree—Fock calculations. Reorganizations of the sigma and pi electronic shells with change in state of the pi system are computed to be large. A gain or loss of a pi electron is accompanied by a sigma energy change of 0.2 a.u. partially due to deformation of the C2s AO and partially due to sigma polarization away from the H atoms in the cation and vice versa in the anion. The large reorganization in the pi distribution is illustrated by the 2pπ exponents: cation 1.68, anion 1.45, ground state 1.59. The total reorganization energy in acetylene (−0.033 a.u. G state→cation; −0.069 a.u. G state→anion) is only 6% of the largest reorganization term: the change in sigma—pi interaction (0.586 and 1.262 a.u., respectively). The success of conventional pi-electron theory then basically depends on cancellation of the sigma and pi reorganization energy terms with the change in the sigma—pi interaction. The Hijcore parameters are found to be nearly independent of pi density providing justification for pi-electron approaches which adjust the pi atomic orbitals according to pi density." @default.
- W2030781154 created "2016-06-24" @default.
- W2030781154 creator A5001686336 @default.
- W2030781154 creator A5041242420 @default.
- W2030781154 date "1967-12-01" @default.
- W2030781154 modified "2023-10-17" @default.
- W2030781154 title "Sigma and Pi Electronic Reorganization in Acetylene" @default.
- W2030781154 cites W1979461555 @default.
- W2030781154 cites W1979636613 @default.
- W2030781154 cites W1983544275 @default.
- W2030781154 cites W1990970942 @default.
- W2030781154 cites W1996608110 @default.
- W2030781154 cites W2007321577 @default.
- W2030781154 cites W2009648773 @default.
- W2030781154 cites W2011079470 @default.
- W2030781154 cites W2013255431 @default.
- W2030781154 cites W2037003298 @default.
- W2030781154 cites W2043891492 @default.
- W2030781154 cites W2063597178 @default.
- W2030781154 cites W2066266133 @default.
- W2030781154 cites W2070045737 @default.
- W2030781154 cites W2086225333 @default.
- W2030781154 cites W2089015106 @default.
- W2030781154 cites W2138869119 @default.
- W2030781154 cites W2170688349 @default.
- W2030781154 cites W2178253001 @default.
- W2030781154 cites W2331582019 @default.
- W2030781154 cites W2622167022 @default.
- W2030781154 cites W4242892478 @default.
- W2030781154 doi "https://doi.org/10.1063/1.1701659" @default.
- W2030781154 hasPublicationYear "1967" @default.
- W2030781154 type Work @default.
- W2030781154 sameAs 2030781154 @default.
- W2030781154 citedByCount "27" @default.
- W2030781154 countsByYear W20307811542021 @default.
- W2030781154 crossrefType "journal-article" @default.
- W2030781154 hasAuthorship W2030781154A5001686336 @default.
- W2030781154 hasAuthorship W2030781154A5041242420 @default.
- W2030781154 hasConcept C113603373 @default.
- W2030781154 hasConcept C121332964 @default.
- W2030781154 hasConcept C139358910 @default.
- W2030781154 hasConcept C145148216 @default.
- W2030781154 hasConcept C147120987 @default.
- W2030781154 hasConcept C178213299 @default.
- W2030781154 hasConcept C178790620 @default.
- W2030781154 hasConcept C181500209 @default.
- W2030781154 hasConcept C184779094 @default.
- W2030781154 hasConcept C185592680 @default.
- W2030781154 hasConcept C189394030 @default.
- W2030781154 hasConcept C2777517455 @default.
- W2030781154 hasConcept C32909587 @default.
- W2030781154 hasConcept C53848692 @default.
- W2030781154 hasConcept C62520636 @default.
- W2030781154 hasConcept C69523127 @default.
- W2030781154 hasConcept C77758465 @default.
- W2030781154 hasConcept C80062241 @default.
- W2030781154 hasConceptScore W2030781154C113603373 @default.
- W2030781154 hasConceptScore W2030781154C121332964 @default.
- W2030781154 hasConceptScore W2030781154C139358910 @default.
- W2030781154 hasConceptScore W2030781154C145148216 @default.
- W2030781154 hasConceptScore W2030781154C147120987 @default.
- W2030781154 hasConceptScore W2030781154C178213299 @default.
- W2030781154 hasConceptScore W2030781154C178790620 @default.
- W2030781154 hasConceptScore W2030781154C181500209 @default.
- W2030781154 hasConceptScore W2030781154C184779094 @default.
- W2030781154 hasConceptScore W2030781154C185592680 @default.
- W2030781154 hasConceptScore W2030781154C189394030 @default.
- W2030781154 hasConceptScore W2030781154C2777517455 @default.
- W2030781154 hasConceptScore W2030781154C32909587 @default.
- W2030781154 hasConceptScore W2030781154C53848692 @default.
- W2030781154 hasConceptScore W2030781154C62520636 @default.
- W2030781154 hasConceptScore W2030781154C69523127 @default.
- W2030781154 hasConceptScore W2030781154C77758465 @default.
- W2030781154 hasConceptScore W2030781154C80062241 @default.
- W2030781154 hasIssue "11" @default.
- W2030781154 hasLocation W20307811541 @default.
- W2030781154 hasOpenAccess W2030781154 @default.
- W2030781154 hasPrimaryLocation W20307811541 @default.
- W2030781154 hasRelatedWork W1972419197 @default.
- W2030781154 hasRelatedWork W1972843563 @default.
- W2030781154 hasRelatedWork W1977242122 @default.
- W2030781154 hasRelatedWork W1986066216 @default.
- W2030781154 hasRelatedWork W2024999454 @default.
- W2030781154 hasRelatedWork W2030781154 @default.
- W2030781154 hasRelatedWork W2068378495 @default.
- W2030781154 hasRelatedWork W2120458816 @default.
- W2030781154 hasRelatedWork W2801304703 @default.
- W2030781154 hasRelatedWork W2915889659 @default.
- W2030781154 hasVolume "47" @default.
- W2030781154 isParatext "false" @default.
- W2030781154 isRetracted "false" @default.
- W2030781154 magId "2030781154" @default.
- W2030781154 workType "article" @default.