Y. Hamada, M. Tsuboi, K. Yamanouchi
Aug 1, 1986
Citations
0
Influential Citations
38
Citations
Journal
Journal of Molecular Structure
Abstract
Abstract The geometrical parameters for the two conformers, gauche ( g ) and trans ( t ), of ethylamine have been determined by a joint analysis of the electron diffraction intensity measured in the present study and the rotational constants reported in the literature. The optimized geometries estimated by an SCF MO calculation with a 4-31G(N*) basis set were also used in the analysis to complement the experimental data. The bond lengths ( r g ) and the bond angels ( r z ) determined are r (CH) av = 1.107(6) A r (CN) t = 1. 470(10)A, r(CN) g = 1.475(10) A r (CC) t = 1.531(6) A r (CC) g = 1.524(6) A , ∠CCN) t = 115.0(3)°, and ∠CCCN g = 109.7(3)°. The uncertainties represent estimated limits of error. The difference between the CCN g and CCN g angles predicted by a previous ab initio calculation is confirmed. The enthalpy difference,Δ H ( g t ), is determined to be 306(200) cal mol −1 using the abundance of the trans conformer, 46(10)%.