[3N01-05] Neutron Measurement/Neutron Facility

[3N03] Molecular force field dependence on the analysis of thermal neutron scattering cross-sections for methylbenzene derivatives

*Yutaka Abe¹, Seiji Tasaki¹, Masahiro Hino¹ (1. Kyoto Univ.)

Keywords:Thermal neutron scattering cross-section, Cold neutron source, Methylbenzene derivatives, Molecular force field

To evaluate molecular force field dependence on the analysis of thermal neutron scattering cross-sections for methylbenzene derivatives, their densities of states are calculated by using four typical force fields (GROMOS54A7, CHARMM36, OPLS-AA, and GAFF). Significant differences are found in librational modes of methyl groups and internal vibrational modes below several dozen meV, which are important for cold neutron production. By comparing with experimental data, CHARMM36 turns out to give the most appropriate results.