The structure directing role of 1,3-diaminopropane in the hydrothermal synthesis of iron(III) phosphate

1,3-Diaminopropane (DAP) was used as a structure-directing agent for the hydrothermal synthesis of an organically templated iron phosphate. During crystallization at 180 oC, iron phosphate (FePO-DAP) with a layered structure was formed after one day. Longer crystallization yielded a mixture of FePO-DAP and leucophosphite, raising the question whether a transformation of FePO-DAP to leucophosphite occurs, or wheter DAP decomposes under hydrothermal conditions resulting in leucophosphite formation. Lattice energy and free energy calculations strongly support the supposition that a decomposition of DAP occurs prior to the formation of leucophosphite.