Cooperative CH··· Interactions in the Crystal Structure of 2,5-Di(3-biphenyl)-1,1-dimethyl-3,4-diphenyl-silole and Its E
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- 作者：Isabella L. Karle ; Raymond J. Butcher ; Mason A. Wolak ; Demetrio A. da Silva Filho ; Manabu Uchida ; Jean-Luc Bré ; das ; Zakya H. Kafafi
- 刊名：Journal of Physical Chemistry C
- 出版年：2007
- 出版时间：July 5, 2007
- 年：2007
- 卷：111
- 期：26
- 页码：9543 - 9547
- 全文大小：308K
- 年卷期：v.111,no.26(July 5, 2007)
- ISSN：1932-7455
文摘
In order to develop a fundamental understanding for the effect of molecular packing on the carrier transportproperties of organic semiconductors, single crystals of 2,5-di-(3-biphenyl)-1,1-dimethyl-3,4-diphenylsilacyclopentadiene (PPSPP) were prepared using the physical vapor transport technique and characterized by X-raycrystallography. There is no evidence of 
- stacking in the PPSPP single-crystal because of the nearlyorthogonal arrangements of the phenyl rings in the biphenyl moieties. Although the PPSPP molecules do nothave any -NH or -OH groups that would provide donors for normal hydrogen bonds, the crystal structurereveals the presence of several CH groups that act as donors for CH··· interactions with nearby phenylgroups in an edge-to-face motif. It is proposed that the cooperativity between several weak CH··· bondsenhances their effects and gives rise to a tighter molecular packing than what would be observed for a typicalmolecular crystal where van der Waals forces dominate. Theoretical electronic-structure calculations indicatethat there is a decoupling between the CH... interactions that stabilize the crystal structure and the electronicinteractions that give the largest electronic couplings defining the preferred electron hopping directions.However, the dense molecular packing between adjacent PPSPP molecules may influence its electron transportproperties in the solid state.
- stacking in the PPSPP single-crystal because of the nearlyorthogonal arrangements of the phenyl rings in the biphenyl moieties. Although the PPSPP molecules do nothave any -NH or -OH groups that would provide donors for normal hydrogen bonds, the crystal structurereveals the presence of several CH groups that act as donors for CH··· interactions with nearby phenylgroups in an edge-to-face motif. It is proposed that the cooperativity between several weak CH··· bondsenhances their effects and gives rise to a tighter molecular packing than what would be observed for a typicalmolecular crystal where van der Waals forces dominate. Theoretical electronic-structure calculations indicatethat there is a decoupling between the CH... interactions that stabilize the crystal structure and the electronicinteractions that give the largest electronic couplings defining the preferred electron hopping directions.However, the dense molecular packing between adjacent PPSPP molecules may influence its electron transportproperties in the solid state.