Refinement of the crystal structures of the La3Ta0.5Ga5.5O14 and La3Nb0.5Ga5.5O14 compounds

被引:28
作者
Dudka, A. P. [1 ]
Mill, B. V. [2 ]
Pisarevsky, Yu. V. [1 ]
机构
[1] Russian Acad Sci, AV Shubnikov Crystallog Inst, Moscow 119333, Russia
[2] Moscow MV Lomonosov State Univ, Moscow 119992, Russia
基金
俄罗斯基础研究基金会;
关键词
DIFFRACTION DATA; REDUCED DATA; NEUTRON-DIFFRACTION; MINIMIZATION METHOD; ELECTRON-DENSITY; LANGASITE FAMILY; X-RAY; ABSORPTION; PARAMETERS; UREA;
D O I
10.1134/S106377450904004X
中图分类号
O7 [晶体学];
学科分类号
0702 ; 070205 ; 0703 ; 080501 ;
摘要
This paper reports on the results of accurate X-ray structural investigations of single crystals La3Ta0.5Ga5.5O14 (a = 8.2260(1) , c = 5.1207(1) , R/R (w) = 1.09%/1.10%, 3868 unique reflections) and La3Nb0.5Ga5.5O14 (a = 8.2237(1) , c = 5.1247(1) , R/R (w) = 1.02%/1.03%, 3735 unique reflections) (space group P321, Z = 1, sinI/lambda vertical bar(max) a parts per thousand 1.34 (-1) for both compounds). Using sets of data with a large number of high-angle reflections makes it possible to reliably compare the crystal structures by applying statistical tests. The structural differences between the La3Ta0.5Ga5.5O14 and La3Nb0.5Ga5.5O14 crystals are weakly pronounced, which correlates with the closeness of their piezoelectric characteristics.
引用
收藏
页码:558 / 567
页数:10
相关论文
共 39 条
[1]   Comparing independently determined structures [J].
Abrahams, SC .
ACTA CRYSTALLOGRAPHICA SECTION A, 1997, 53 :673-675
[3]   Origin of piezoelectricity for langasite A3Ga5SiO14 (A = La and Nd) under high pressure [J].
Araki, N. ;
Ohsato, H. ;
Kakimoto, K. ;
Kuribayashi, T. ;
Kudoh, Y. ;
Morikoshi, H. .
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 2007, 27 (13-15) :4099-4102
[4]   EXTINCTION WITHIN LIMIT OF VALIDITY OF DARWIN TRANSFER EQUATIONS .1. GENERAL FORMALISMS FOR PRIMARY AND SECONDARY EXTINCTION AND THEIR APPLICATION TO SPHERICAL CRYSTALS [J].
BECKER, PJ ;
COPPENS, P .
ACTA CRYSTALLOGRAPHICA SECTION A, 1974, A 30 (MAR) :129-147
[5]  
Belokoneva E. L., 1985, CRYSTAL CHEM SYSTEMA, P140
[6]  
Belokoneva EL, 2000, RUSS J INORG CHEM+, V45, P1642
[7]   The charge density of urea from synchrotron diffraction data [J].
Birkedal, H ;
Madsen, D ;
Mathiesen, RH ;
Knudsen, K ;
Weber, HP ;
Pattison, P ;
Schwarzenbach, D .
ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, 2004, 60 :371-381
[8]   AN EMPIRICAL CORRECTION FOR ABSORPTION ANISOTROPY [J].
BLESSING, RH .
ACTA CRYSTALLOGRAPHICA SECTION A, 1995, 51 :33-38
[9]   Crystal structure of La3Nb0.5Ga5.5O14 at 20 K [J].
Chernaya, T. S. ;
Kazantsev, S. S. ;
Molchanov, V. N. ;
Verin, I. A. ;
Blomberg, M. K. ;
Maksimov, B. A. ;
Simonov, V. I. .
CRYSTALLOGRAPHY REPORTS, 2006, 51 (01) :23-28
[10]   Obtainment of precise experimental data on diffractometers with 2D and point detectors [J].
Dudka, A. P. .
CRYSTALLOGRAPHY REPORTS, 2008, 53 (04) :717-720