A. Borrmann et Ro. Jones, STRUCTURES AND ENERGY BARRIERS IN SMALL HYDROCARBON MOLECULES A DENSITY-FUNCTIONAL STUDY, Chemical physics letters, 252(1-2), 1996, pp. 1-8
Density functional calculations with simulated annealing have been per
formed for a range of small hydrocarbon molecules (CH, CH2, C2H2, C2H4
, C3H6, C3H8). In addition to the geometries and relative energies of
low-lying states, we focus on the barriers for internal rotation about
both single and double bonds. There is satisfactory overall agreement
with experiment using both local spin density and gradient-corrected
non-local energy functionals, so that energy surfaces provided by DF c
alculations on structural units should then provide a useful database
for parameterizing the forces in extended systems, such as organic pol
ymers.