On the problem whether the van der Waals parameters a and b depend on
temperature，different literature
gives different answer，and even the same literature in different pages
gives contrary answer. In thermody
namics，they are approximately treated as constants due to matching the
thermodynamic coordinates of the critical
point and van der Waals equation of state can be expressed as the
corresponding state law. Once the parameters a
and b depend on the temperature，the corresponding state law does not hold
true，and other peculiarities of the van
der Waals equation of state is lost accordingly. In statistical
mechanics，we usually obtain a Virial expansion of the
equation of state; once the van der Waals equation is used to interpolate
to this expansion，they are temperaturedependent
except some special cases. Therefore，the different statements on
temperature dependence of the van der
Waals a and b parameter in thermodynamics and statistical mechanics are in
fact originates from implicit assumption
of the same application domain of the van der Waals equation of state in
two different disciplines.
Just Accepted
