Abstract
Crystal structures of the compounds Ca9 R(VO4)7 (R = Tb (I), Dy (II), Ho (III), and Y (IV) have been studied by the method of the full-profile analysis. All the compounds are crystallized in the trigonal system (sp. gr. R 3 c, Z = 6) with the unit-cell parameters (I) a = 10.8592(1), c = 38.035(1), V = 3884.2(2) Å3; (II) a = 10.8564(1), c = 38.009(1) Å, V = 3879.6(2) Å3, (III) a = 10.8565(1) and c = 37.995(1) Å, V = 3878.3(2) Å3, and (IV) a = 10.8588(1), c = 37.995(1) Å, V = 3879.9(2) Å3. In structures I–IV, rare earth and calcium cations occupy three positions—M(1), M(2), and M(5). Rare earth cations occupy the R 3+ positions almost in the same way: 2.7–2.6(2) cations in the M(1) position; 2.7–2.3(2) cations in the M(2) position, and 0.6–1.0(1) cation in the M(5) position. At the same time, the occupancy of the M(5) position regularly increases with a decrease of the R 3+ radius.
Similar content being viewed by others
References
R. Gopal and C. Calvo, Z. Kristallogr. 137, 67 (1973).
B. Dickens, L. W. Schroeder, and W. E. Brown, J. Solid State Chem. 10, 232 (1974).
L. H. Brixner and P. A. Flournoy, J. Electrochem. Soc. 112, 303 (1965).
V. Pelova, K. Kynev, and G. Gochev, J. Mater. Sci. Lett. 14, 330 (1995).
B. I. Lazoryak, V. N. Golubev, E. A. Vovk, et al., Zh. Prikl. Spektrosk. 53(5), 754 (1990).
A. A. Fotiev, B. V. Shul’gin, A. S. Moskvin, and F. F. Gavrilov, Vanadium Crystal Phosphors (Nauka, Moscow, 1976).
B. I. Lazoryak, L. O. Dmitrienko, and S. V. Grechkin, Zh. Neorg. Khim. 35(5), 1095 (1990).
A. A. Belik, V. A. Morozov, S. S. Khasanov, and B. I. Lazoryak, Kristallografiya 42(5), 818 (1997).
H. M. Rietvield, Acta Crystallogr. 22, 151 (1967).
F. Izumi, The Rietveld Method, Ed. by R. A. Young (Oxford Univ., Oxford, 1993), Ch. 13.
Y._I. Kim and F. Izumi, J. Ceram. Soc. Jpn. 102, 401 (1994).
C. Calvo and R. Gopal, Am. Mineral. 60, 120 (1975).
B. N. Viting, Candidate’s Dissertation in Chemistry (Moscow, Moscow State Univ., 1990).
B. I. Lazoryak, Usp. Khim. 65(4), 307 (1996).
R. D. Shannon, Acta Crystallogr., Section B: Struct. Crystallogr. Cryst. Chem. 32, 751 (1976).
B. I. Lazoryak, V. A. Morozov, A. A. Belik, et al., J. Solid State Chem. 122(1), 15 (1996).
V. A. Morozov, Candidate’s Dissertation in Chemistry (Moscow, Moscow State Univ., 1996).
Author information
Authors and Affiliations
Additional information
__________
Translated from Kristallografiya, Vol. 45, No. 3, 2000, pp. 432–437.
Original Russian Text Copyright © 2000 by Belik, Morozov, Kotov, Khasanov, Lazoryak.
Rights and permissions
About this article
Cite this article
Belik, A.A., Morozov, V.A., Kotov, R.N. et al. Crystal structure of double vanadates Ca9 R(VO4)7. II. R = Tb, Dy, Ho, and Y. Crystallogr. Rep. 45, 389–394 (2000). https://doi.org/10.1134/1.171204
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1134/1.171204