Struktur und Schwingungsspektrum des α-Undekawolframatophosphats Na₂[N(CH₃)₄]₄HPW₁₁O₃₉ · 7H₂O / Structure and Vibrational Spectrum of the α-Undecatungstophosphate Na₂[N(CH₃)₄]₄HPW₁₁O₃₉ · 7H₂O

Abstract

The crystal structure of the compound Na 2 [N(CH 3 ) 4 ] 4 HPW 11 O 39 · 7H 2 O was solved by X-ray diffraction. It crystallizes in the space group C2/m with lattice parameters a= 23.895 Å, b = 11.417 Å, c = 28.930 Å, β= 126.0°. The distances between the tungsten atoms and the kind of bridging by oxygen atoms prove the α-isomer. The differences between the vibration spectra of α-undecatungsto-phosphate and α-dodecatungstophosphate are discussed