Five Stereoactive Orbitals on Silicon: Charge and Spin Localization in the n-Si4Me10-center dot Radical Anion by Trigonal Bipyramidalization

0394749 - ÚOCHB 2014 RIV US eng J - Článek v odborném periodiku
MacLeod, M. K. - Michl, Josef
Five Stereoactive Orbitals on Silicon: Charge and Spin Localization in the n-Si4Me10-center dot Radical Anion by Trigonal Bipyramidalization.
Journal of Physical Chemistry Letters. Roč. 4, č. 10 (2013), s. 1649-1653. ISSN 1948-7185
Institucionální podpora: RVO:61388963
Klíčová slova: electronic-structure * absorption-spectroscopy * polysilanes
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 6.687, rok: 2013

RIUMP2/def2-TZVPPD calculations show that in addition to its usual conformation with charge and spin delocalized over the Si backbone, the isolated Si4Me10-center dot radical anion also has isomeric conformations with localized charge and spin. A structure with localization on a terminal Si atom has been examined in detail. In vacuum, it is calculated to lie 11.5 kcal/mol higher in energy than the charge-and-spin delocalized conformation, and in water the difference is as little as 1.6 kcal/mol. According to natural orbital and localized orbital analyses, the charge-and-spin-carrying terminal Si atom uses five stereoactive hybrid orbitals in a trigonal bipyramidal geometry. Four are built mostly from 3s and 3p atomic orbitals (AOs) and are used to attach a Si-3(CH3)(7) and three CH3 groups, whereas the larger equatorial fifth orbital is constructed from 4s and 4p AOs and acts as a nonbonding (radical) hybrid orbital with an occupancy of about 0.65 e.
Trvalý link: http://hdl.handle.net/11104/0223102