Characterization and 31P NMR study of [X2{PW3O9.5(O2)3(OH)0.5(OH2)}4]8- (X=K+, Rb+, NH4+)

INOR 711

Shinya Kitaura, Kiyotaka Kihara, Masato Hashimoto, mh1043@sys.wakayama-u.ac.jp, and Seichi Okeya, okeya@sys.wakayama-u.ac.jp. Department of Material Science and Chemistry, Faculty of Systems Engineering, Wakayama University, Sakaedani 930, Wakayama, 640-8510, Japan
A series of novel peroxophosphatotungstates, [X2{PW3O9.5(O2)3(OH)0.5(OH2)}4]8- (X=K+, Rb+, NH4+) were synthesized as guanidinium salts and characterized by X-ray and 31P NMR. In each anion, four W3P1 units form a ring-shaped structure by sharing their corners, and two X cations are accommodated in the cavity at the center (see figure). The X-ray structural analysis showed that these compounds were isostructural. The solid state 31P NMR of the anion (X=K+) exhibited signals around –6 ppm. A 31P signal in aqueous solution (ca. –6 ppm), which probably corresponded to that in the solid state, appeared only in narrow pH range just before crystallization. Detailed structural features and formation behaviors will be discussed.

 

Polyoxometalates and Related Clusters in Chemistry and Nanoscience
7:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Inorganic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007