Surface tension measurement and molecular simulation for new low global warming potential refrigerants R1132(E) and R1132a

This study performed surface tension measurements assisted by molecular simulations for new candidate refrigerants R1132(E) and its isomer R1132a, which exhibit extremely low global warming potentials. Because the measured saturation density required for the surface tension measurement by the differential capillary rise method is insufficient at low temperatures, the density data was extrapolated by molecular simulations. In the process, quantum chemical and molecular dynamics simulations were performed to reproduce the vapor–liquid equilibrium state, and the accuracy of the obtained molecular force fields was verified by comparing them with the measured data. Based on the obtained surface tension data, validated temperature correlation equations were proposed for R1132(E) and R1132a, respectively, validated in the temperature range from 209 K to 225 K. Furthermore, their parachors, which relate surface tension to saturation density, were determined from the above data as 116.1 and 116.7 for R1132(E) and R1132a, respectively.