Gas-phase structures of sterically crowded disilanes studied by electron diffraction and quantum chemical methods: 1,1,2,2-tetrakis(trimethylsilyl) disilane and 1,1,2,2-tetrakis(trimethylsilyl)dimethyldisilane

Jan Schwabedissen, Paul D. Lane, Sarah L. Masters*, Karl Hassler, Derek A. Wann

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


The gas-phase structures of the disilanes 1,1,2,2-tetrakis(trimethylsilyl) disilane [(Me3Si)2HSiSiH(SiMe3)2] (1) and 1,1,2,2-tetrakis(trimethylsilyl)dimethyldisilane [(Me 3Si)2MeSiSiMe(SiMe3)2] (2) have been determined by density functional theoretical calculations and by gas electron diffraction (GED) employing the SARACEN method. For each of 1 and 2 DFT calculations revealed four C2-symmetric conformers occupying minima on the respective potential-energy surfaces; three conformers were estimated to be present in sufficient quantities to be taken into account when fitting the GED data. For (Me3Si)2RSiSiR(SiMe3)2 [R = H (1), CH3 (2)] the lowest energy conformers were found by GED to have RSiSiR dihedral angles of 87.7(17)° for 1 and -47.0(6)° for 2. For each of 1 and 2 the presence of bulky and flexible trimethylsilyl groups dictates many aspects of the geometric structures in the gas phase, with the molecules often adopting structures that reduce steric strain.

Original languageEnglish
Pages (from-to)10175-10182
Number of pages8
JournalDalton Transactions
Issue number26
Publication statusPublished - 14 Jul 2014

Bibliographical note

© Royal Society of Chemistry 2014. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details. Date of Acceptance: 19/05/2014

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