ES22-Petras

Author: Petras, Hayley R. - University of Iowa

Title: Diatomic potential energy surfaces and the effect of temperature

Abstract: We present data showing the effect of finite electronic temperature on the potential energy surfaces of first row homodiatomic molecules. Our approach is to use finite temperature full configuration interaction to first evaluate how the surfaces change with temperature. We will show temperature dependent surfaces for lithium, beryllium, boron, carbon, oxygen and fluorine all in the STO-3G basis set. We find that each diatomic exhibits a set of a qualitative features that are similar across the first row diatomics. In addition, we explore how strong correlation changes with temperature in N2/cc-pVDZ by analyzing the particle population on the density matrix throughout the piecewise interaction picture density matrix quantum Monte Carlo (PIP-DMQMC) simulations. Finally, we will analyze how the strength of the bond changes with temperature by fitting the temperature dependent surfaces to a Harmonic Oscillator model, and calculating the associated force constants for all the diatomics.

Other authors: Van Benschoten, William Z. (University of Iowa); Shepherd, James J. (University of Iowa)