Intermolecular potential parameters for ammonia have been determined for the Stockmayer-Kihara function using experimental second virial coefficient, diffusivity and viscosity data of binary mixtures with argon, methane, nitrogen, and oxygen. The parameters Uo/k = 215 PK, core-to-core) = 2.70 A and a* = 0.2 reproduce essentially all of the data nearly w~t h~n expermental error and accurately reproduce pure ammonia transport properties. Upon considering both physical and chemical contributions to the second virial coefficient of ammonia, the apparent standard-state hydrogen-bond enthalpy for chemical dimerization is -3.2 kcal/mole while the vibrational entropy change is 20.2 cal/mole OK, indicating weak association.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.