A test particle model potential for formamide and molecular dynamics simulations of the liquid

A test particle model (T-model) potential is derived for interacting rigid formamide (HCONH2) molecules and applied in MD simulations of the liquid phase. The most important features of the dimers predicted by the T-model potential are checked by large basis set SCF calculations. The most stable dimer is the cyclic arrangement with an interaction energy of −10.91 kcal/mol at the SCF level and −11.72 kcal/mol for the T model. However, the dominating molecular arrangements in the liquid phase are found to be linear-like structures. The computed thermodynamic, dynamic, and structural properties of the liquid are compared with available theoretical and experimental data.