Jc. Rainwater et Rf. Snider, THE EQUILIBRIUM PAIR DISTRIBUTION FUNCTION OF A GAS - ASPECTS ASSOCIATED WITH THE PRESENCE OF BOUND-STATES, The Journal of chemical physics, 99(11), 1993, pp. 9111-9121
At thermal equilibrium the momentum distribution of atoms in a gas is
usually assumed to be Maxwellian, whether classically or quantally. Ho
wever, if an atom is bound in a diatomic molecule, the atom's momentum
distribution is non-Maxwellian. This paper explores the consequent si
nglet and pair particle distribution functions in a gas having both un
bound atoms and bound pairs of atoms. Comment is made on the range of
behavior associated with whether the chemical equilibrium constant for
diatom formation is small or large. Calculations of distribution func
tions and their moments for atoms which are members of dimers are pres
ented for some specific model potentials.