Structure of disiloxane: A semiempirical and Post-Hartree–Fock study
✍ Scribed by Gábor I. Csonka; Miklós Erdösy; József Réffy
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 992 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0192-8651
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The semiempirical (MNDO, AM1, and PM3) and ab initio predicted structure of disiloxane is studied with a series of basis sets and inclusion of electron correlation at MP2, MP3, MP4, CCD, CCSD, and CCSD(T) levels. The calculated molecular geometry and barrier to linearization of the SiOSi bond angle are compared with previous theoretical and experimental values. Our results show that the calculated barrier to linearization is very sensitive to the number of polarization functions in the basis set. We also investigate the coupling between the SiOSi bond angle and the SiO bond length and calculate the Mulliken and electrostatic potential‐derived charges. For comparison purposes we also calculate the molecular geometry, the barrier to linearization of the SiOSi bond angle, and the atomic charges in hexamethyldisiloxane. © 1994 by John Wiley & Sons, Inc.
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