Standard Heat of Formation of Uranium Compounds

tzeng89

There is a bit of data and literature that shows the standard heats of formation for various uranium compounds including UO3, U3O8 UF6 etc.
However there appears to be nothing on ammonium diuranate which is one of the most common intermediate forms produced by precipitation. The ADU as it is commonly known is then heated until a reaction occurs and the solid releases its ammonia to ultimately produce U3O8. Is the only way to get the Heat of reaction to know the Standard Heats of formation of the products and reactants? If yes, where is the best place to find the Heat of formation and specific heat values for ammonium diuranate?
Can anyone help?