Stereochemical effects in the mass spectra of some cyclopropylsilanes explained by the MNDO molecular orbital method. I. Silicon‐oxygen interactions

K. Vékey, Árpád Somogyi, József Tarnás, Gabriella Pócsfalvi

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Large differences have been found between the mass spectra of cis‐ and trans‐1‐carbomethoxy‐2‐trimethylsilylcyclopropane. To help in explaining these differences, quantum chemical calculations were performed by the MNDO method on the neutral molecules, on the vertical and adiabatic molecular ions and also the [M – methyl]+ ions. To evaluate the results, heats of formation, bond orders, molecular geometry, spin and charge densities and orbital coefficients were used. These indicate the formation of a very strong bonding interaction between silicon and oxygen in the molecular ion of the cis but not the trans isomer, leading to spontaneous methyl loss and a stabilization energy of ∼ 2.6 eV.

Original languageEnglish
Pages (from-to)869-875
Number of pages7
JournalOrganic Mass Spectrometry
Volume27
Issue number8
DOIs
Publication statusPublished - 1992

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Molecular orbitals
molecular ions
mass spectra
molecular orbitals
Ions
heat of formation
isomers
stabilization
interactions
Silicon
Charge density
orbitals
Isomers
silicon
oxygen
coefficients
Stabilization
geometry
Hot Temperature
Oxygen

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Medicine
  • Instrumentation

Cite this

Stereochemical effects in the mass spectra of some cyclopropylsilanes explained by the MNDO molecular orbital method. I. Silicon‐oxygen interactions. / Vékey, K.; Somogyi, Árpád; Tarnás, József; Pócsfalvi, Gabriella.

In: Organic Mass Spectrometry, Vol. 27, No. 8, 1992, p. 869-875.

Research output: Contribution to journalArticle

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