Crystalline ethane-1,2-diol does not have intra-molecular hydrogen bonding: Experimental and theoretical charge density studies
✍ Scribed by Deepak Chopra; Tayur N. Guru Row; Elangannan Arunan; Roger A. Klein
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 654 KB
- Volume
- 964
- Category
- Article
- ISSN
- 0022-2860
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✦ Synopsis
The X-ray structure and electron density distribution of ethane-1,2-diol (ethylene glycol), obtained at a resolution extending to 1.00 Å À1 in sin h/k (data completion = 100% at 100 K) by in situ cryocrystallization technique is reported. The diol is in the gauche (g 0 Gt) conformation with the crystal structure stabilised by a network of inter-molecular hydrogen bonds. In addition to the well-recognized O-HÁÁÁO hydrogen bonds there is topological evidence for C-HÁÁÁO inter-molecular interactions. There is no experimental electron density based topological evidence for the occurrence of an intra-molecular hydrogen bond. The OÁÁÁH spacing is $0.45 Å greater than in the gas-phase with an O-HÁÁÁO angle close to 90°, calling into question the general assumption that the gauche conformation of ethane-1,2-diol is stabilised by the intra-molecular oxygen-hydrogen interaction.