کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1411581 | 1501868 | 2009 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A noncentrosymmetric crystal structure of a zwitterionic compound, pyridinium 5,7-dihydro-5,7-dioxo-6H-cyclopenta[b]pyridin-6-ylide, realized by weak hydrogen bonds A noncentrosymmetric crystal structure of a zwitterionic compound, pyridinium 5,7-dihydro-5,7-dioxo-6H-cyclopenta[b]pyridin-6-ylide, realized by weak hydrogen bonds](/preview/png/1411581.png)
Crystal structures of pyridinium 1,3-dihydro-1,3-dioxo-2H-inden-2-ylide (PI) of a zwitterionic molecule and its nitrogen substituted compounds, 4N-PI and 5N-PI, were solved with X-ray diffraction analyses. Whereas PI and 5N-PI showed centrosymmetric crystal structures, 4N-PI demonstrated a noncentrosymmetric crystal structure where all the molecules orient to almost the same direction. To elucidate the stability of such a polarized structure, we examined interatomic close contacts among the nearest neighbor molecules in the crystals and calculated intermolecular interaction energies with relation to those contacts. As a result, the noncentrosymmetric crystal structure of 4N-PI turns out to be realized by a weak hydrogen bond in the C–H···N manner formed only in the case of this compound.
Journal: Journal of Molecular Structure - Volume 920, Issues 1–3, 28 February 2009, Pages 52–60