Raman spectroscopy and crystal structure investigation of solvo- and ionothermally prepared microporous metal-aluminophosphates with the laumontite framework structure

摘要

Microporous iron(II)- and manganese(II)-alu-minophosphates zeotypes with the laumontite framework topology were prepared under solvothermal and iono-thermal synthesis conditions at 453 and 433 K. The structures of (C_3N_2H_5)_(7.5)[Al_(16.5)Fe_(7.5)~IIP_(24)0_(96)] and of (C_3N_2H_5)_(5.7)[Al_(18.3)Mn_(5.7)~(II)P_(24)0_(96)] were determined using single-crystal X-ray structure analysis and spectroscopic results. The metalophosphate framework structures are characterized by one-dimensional: channel systems with template cations located in buckled 10-rings. 31% and 24% of aluminium at the tetrahedral positions were replaced by iron and manganese, respectively. Imidazolium acts as structure directing agent in the synthesis and as charge balancing, organic cation in the structure. Ionic liquids used as solvents in the synthesis procedure can significantly improve the crystal quality. Raman spectroscopy reveals that the imidazo-lium-based solvent additionally acts as structure directing agent. The choice of the template molecule and of the solvent determines the degree of the transition metal substitution