A conformational analysis of 4,4'-bipyridinium dication

✍ Scribed by Ellak Von Nagy-Felsobuki

• Publisher: Elsevier Science
• Year: 1986
• Tongue: English
• Weight: 269 KB
• Volume: 127
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(86)80266-4

✦ Synopsis

A conformational analysis of the 4,4'-bipyridinium dication has been investigated using the results from 10 ab initio STO-3G calculations in which the inter-ring bond length was optimized at each torsion angle. The most reliable calculation yields: a lowest energy conformer with an equilibrium torsional angle of 45.3" and inter-ring (R,_,) bond length of 0.152 nm; a barrier height of 5.86 kJ mol-'. An examination of the fitted Fourier series indicates that half of the theoretical data points effectively reproduced the more extensive surface. Furthermore, a comparison of the calculations and fitted surfaces indicate that a rigid rotor is an excellent approximation for this molecule.