Hydrothermal Synthesis and Characterization of Two Mixed Valence Piperazine–Vanadium Phosphates: (C4H12N2)(H3O)[(VOPO4)4(H2O)H2PO4]·3H2O and (C4H12N2)[(VO)(VO2)2(H2O)(PO4)2]

✍ Scribed by Junghwan Do; Ranko P. Bontchev; Allan J. Jacobson

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 488 KB
• Volume: 154
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8872

✦ Synopsis

Two new phases, (C 4 H 12 N 2 )(H 3 O)[(VOPO 4 ) 4 (H 2 O)H 2 PO 4 ] ' 3H 2 O (1) and (C 4 H 12 N 2 )[(VO)(VO 2 ) 2 (H 2 O)(PO 4 ) 2 ] (2) have been synthesized hydrothermally and characterized by single crystal X-ray di4raction, thermogravimetric analysis, and magnetic susceptibility. Compound 1 has an open-framework structure and is closely related to (VO) 2 (PO 4 ) 2 H 2 PO 4 ' N 2 C 2 H 10 , whereas compound 2 has layered structure containing discrete trinuclear [V 3 O 13 (H 2 O)] corner-sharing units. In both structures the V atoms are mixed-valence, V IV and V V , with octahedral and trigonal bipyramidal geometry. Crystal data: (C 4 H 12 N 2 )(H 3 O) [(VOPO 4 ) 4 (H 2 O)H 2 PO 4 ] ' 3H 2 O 1, monoclinic, space group P2/n (No. 13), a ‫)7(8446.9؍‬ A > , b ‫؍‬ 8.8770(7) A > , c ‫؍‬ 14.813(1) A > , ‫؍‬ 91.936(2)3, Z ‫؍‬ 4, R1 ‫؍‬ 0.0717; (C 4 H 12 N 2 ) [(VO)(VO 2 ) 2 (H 2 O) (PO 4 ) 2 ] 2, triclinic, space group P1 (No. 2); a ‫؍‬ 6.1650(5) A > ,