English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Density Functional Theory calculations on E(SbMe 2 ) 2 , E = O, S or Se, Me = CH 3 , indicate that the equilibrium structures are syn-syn or near syn-syn conformers with over-all C 2  symmetry. The barriers restricting rotation about E-Sb bonds are very low, the equilibrium values for the dihedral angles ϕ(Sb-E-Sb-lp) where lp denotes the direction of the electron lone pair on one of the Sb atoms are probably less than 45°. The calculations further indicate the existence of syn-anti conformers some 4 kJ mol -1  above the more stable syn-syn. Gas electron diffraction data show that both conformers are present in gaseous O(SbMe 2 ) 2 , while the presence of the syn-anti conformer in gaseous Se(SbMe 2 ) 2  is uncertain; least-squares refinements yielded the mole fraction χ = 0.27(18). The Sb-O and Sb-Se bond distances are 197.6(14) and 255.1(5) pm respectively, the valence angles of the syn-syn conformers are &lt;SbOSb = 122.3(16)° and &lt;SbSeSb = 96.3(11)°. It is suggested that the wide &lt;SbOSb angle is due to across-angle repulsion between the Sb atoms.

zeitschrift für naturforschung b

The Molecular Structures and Conformational Preferences of Bis(dimethylstibyl)- Oxane, -Sulfane and -Selane, E(SbMe 2 ) 2 , E = O, S or Se, Me = CH 3 , by Density Functional Theory Calculations and Gas Electron Diffraction