This function calculates the specific heat capacity of R134a at constant volume from the state record (e.g., use setState_phX function for input). The specific heat capacity is modelled by the fundamental equation of state of Tillner-Roth and Baehr (1994).
Please note, that the function can also be called in the two-phase region, but the output is not continuous for a phase transition (see Tillner-Roth and Baehr, 1994). Values in two-phase region are considerably higher than in one-phase domain. The following figure just shows one-phase properties.