Molecular simulation of Mn(II)-substituted aluminophosphate MnAPO-14

The structure of manganese(II)-substituted aluminophosphate MnAPO-14 with AFN zeotype has been investigated by computational simulation in Cerius ² package. Starting from reported structure of MnAPO-14, total 28 theoretical models of Mn-substituted AFN have been built and optimized to obtain their stable conformation. In terms of the host-guest non-bonding interaction and the framework energies, the Mn(II)-substituted sites and the bonded sites of two H₂O molecules can be well predicted for MnAPO-14. The simulated structure is in good a-greement with that of experimental MnAPO-14. Calculation results suggest that the replacement site of Al by Mn(II) atom in AFN is dramatically effected by the guest molecules of organic templating resided in the channels, which is corresponding to the host-guest charge-density matching principle. This work will be helpful for the better understanding the structures of metal-substituted microporous materials.