The role of inorganic acidity on templated vanadate composition and dimensionality

• Analysis of hydrothermal crystal growth formation principles.
• Hydrothermal syntheses of organically templated vanadium phosphites and vanadium selenites.
• Non-covalent interaction index (NCI) calculations.

Compositional and structural differences in two organically templated vanadate compounds are directly ascribed to the acidity of the primary building units from which they are constructed. [C6H16N2][(VO)2(HPO3)3] and [C6H16N2][VO(SeO3)(HSeO3)]2 were synthesized under analogous conditions with either phosphorous or selenous acid. The acidities of these primary building units are reflected in both their relative protonation states and the compositions of the resulting solids. Differences in intermolecular interactions cause deviations in dimensionality of the resulting [(VO)2(HPO3)3]n2n−[(VO)2(HPO3)3]n2n− layers and [VO(SeO3)(HSeO3)]nn−[VO(SeO3)(HSeO3)]nn− chains, as identified and visualized using non-covalent interaction index calculations. Steric repulsions between adjacent [VO(SeO3)(HSeO3)]nn−[VO(SeO3)(HSeO3)]nn− chains preclude the formation of two-dimensional layers, such repulsions are absent in [C6H16N2][(VO)2(HPO3)3], as visualized using non-covalent interaction index calculations.

Differences in acidity between phosphorous and selenous acids cause marked differences in composition, structure and dimensionality between [C6H16N2][(VO)2(HPO3)3] and [C6H16N2][VO(SeO3)(HSeO3)]2, as visualized using non-covalent interaction index calculations.Figure optionsDownload as PowerPoint slide