Abstract
The geometries of the lowest singlet and triplet states of silacyclobutadiene have been optimized at the double-zeta (DZ) and double-zeta (DZ +d) self-consistent-field (SCF) level of theory. Silacyclobutadiene has a planar asymmetric closed-shell ground state. The ground-state C—C and C—Si bond lengths are in good agreement with standard values, indicating that this state is closely analogous to the ground state of cyclobutadiene. The calculated DZ +d SCF harmonic vibrational frequencies support this analogy. The lowest triplet state of silacyclobutadiene is found by configuration-interaction calculations to lie only ca. 5 kcal mol–1 above the ground state, much lower than the established value of 23 kcal mol–1 for the singlet–triplet separation in cyclobutadiene. The overall stability and singlet–triplet separation of silacyclobutadiene are discussed in terms of bond energies and π-system aromaticity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.