Comment on constrained molecular dynamics of macromolecules

Molecular dynamics calculations for a free decane with and without bond and bond angle constraints show that the effect of freezing the bond angles is bigger—or of the same order of magnitude as the solvent effect from other decane molecules in a corresponding liquid decane. Especially the dynamical behavior, given by the trans–gauche transition rate is changed by the bond angle constraints, whereas only very small differences are obtained by freezing the bond lengths. The statistical means are first obtained after averaging over time intervals of the order nanoseconds.