Some simple basis sets for accurate 13c chemical shift calculations
โ Scribed by D.B. Chesnut; C.K. Foley
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 578 KB
- Volume
- 118
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
โฆ Synopsis
Two relauvely simple basis XLS reproduce '"C chemical shirls in small mokules and simple lirst-row hydrides LO an UIXUKI~ comparable IO or bclrer than previous more exlcnsive bases_ The bases are esse~~tielly u-iple-zela valence sets with one set of d polariza~on functions on heavy atoms and double-or lriple-ZEN witi no polarization on hydrogen_ Hydrogen shifts are marginally aoxpclble on an absolute scale bur surpn~ingly good on a reln~~ve scale
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Calculations of 13C chemical shifts in some simple hydrocarbons have been carried out using the GIAO approach in the MINDOW semiempirical formalism. In order to achieve reasonable agreement with experiment it is necessary to modify (increase) the vacant orbital energies in the MIND0/3 calculation in
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