Solid thorium arsenides

There is no justification in [1960FIL/TEK] for the stoichiometry and the equilibrium constant is therefore not accepted by this review. The only conclusion to be drawn from this study is qualitative, that complexes are formed in the Th(IV)-pyrophosphate system. 

Dissolution of Th2(P04)(P207) and solid solutions of (Th,Pu)2(P04)(P207) have been studied by [2002ROB/DAC], but no information on thermodynamic data is given. The dissolution of monazite in carbonate media is discussed in [2002ABD], but here also there is no thermodynamic information. 

The phase diagram of the Th-As system is still quite poorly defined, except for the Th-rich region, which was studied in detail by Benz [1968BEN]. There are three compounds, whose compositions and stiuctures are given in Table X-4. The diarsenide has two forms, with a transformation temperature of ca. 1373 K [1966HUL2]. 

The only studies of thermodynamic data for thorium arsenides are the measurements of the heat capacities of ThAs(cr) and Th3As4(cr) from 5 to 300 K by 

Phase Symmetry, Space Group Structural type Lattice parameters (A) Reference 

---