Berechnung des zweiten Virialkoeffizienten B(T) für gasförmigen molekularen Wasserstoff im Temperaturintervall von 1 K bis 3000 K

Abstract

The second virial coefficient B(T) of hydrogen (H2) has been calculated at temperatures over the range 1 K to 3000 K using the Woolley potential function. The potential constants ε/k = 28,79 K, rm = 0,34473 nm, e1 = 0,01 have been determined from the B(T)‐data of Michels et al. (1959). The calculated second virial coefficients B(T) agree very well with the available experimental data over the whole temperature range from 13 K to 3000 K. A new method of calculating second virial coefficients has been suggested for low temperatures based on the representation of (y–y0)/(x–x0) vs x by a straight line (x = T1/2, y = T5/4 B).

The exact classical vibrational-rotational partition function for the Woolley potential: calculations of the equilibrium constants for the formation of Ar-Ar and Mg-Mg

“…This potential is of particular interest, since it represents a LJ(12,6) potential deformed by an additional parameter. Moreover, it leads to analytical formulae for a variety of related quantities such as the second and third virial coefficients (Artym 1975), and it has recently been used to obtain very accurate values of the second virial coefficient of H2 (Artym and Kliem 1991). Secondly, we show how its additional parameter allows the Woolley potential to be fitted to a more realistic potential by matching the total number of rovihrational states supported by both potentials.…”