Crystal structure of new compound (Rb,K)2Cu3(P2O7)2
- Authors: Krivovichev S.V.1,2, Chernyat’eva A.P.1
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Affiliations:
- Institute of Earth Sciences
- Grebenshchikov Institute of Silicate Chemistry
- Issue: Vol 42, No 4 (2016)
- Pages: 327-336
- Section: Article
- URL: https://journals.rcsi.science/1087-6596/article/view/215607
- DOI: https://doi.org/10.1134/S1087659616040088
- ID: 215607
Cite item
Abstract
A new compound of (Rb,K)2Cu3(P2O7)2 is obtained by high-temperature reactions from a mixture of RbNO3, KNO3, Cu(NO3)2, and (NH4)4P2O7. The crystal structure was solved by direct methods and refined to R1 = 0.056 for 5022 independent reflections. The compound belongs to a rhombic crystal system, P212121, Z = 8, a = 9.9410(7) Å, b = 13.4754(6) Å, c = 18.6353 (3) Å, and R = 0.056. The basis of the structure is a complex copper-phosphate skeleton of the composition of [Cu3(P2O7)2]2–, which can be regarded as consisting of two types of heteropolyhedral layers parallel to the (001) plane. The layers are alternated with each other, forming a frame, in the cavities of which the positions of alkali cations are located, statistically populated with K+ and Rb+ ions. Based on the refined populations of the positions of alkali cations, an exact chemical formula of the compound can be written as Rb1.28K0.72Cu3(P2O7)2. The compound is the most complex among those known to this day of the composition of A2IB3II(P2O7)2 (A = Li, Na, K, Rb, or Cs; B = Ni, Cu, or Zn).
About the authors
S. V. Krivovichev
Institute of Earth Sciences; Grebenshchikov Institute of Silicate Chemistry
Author for correspondence.
Email: s.krivovichev@spbu.ru
Russian Federation, Universitetskaya nab. 7/9, St. Petersburg, 199034; nab. Makarova 2, St. Petersburg, 199034
A. P. Chernyat’eva
Institute of Earth Sciences
Email: s.krivovichev@spbu.ru
Russian Federation, Universitetskaya nab. 7/9, St. Petersburg, 199034