TY  - JOUR
AU  - Sazonov, Andrew
AU  - Hutanu, Vladimir
AU  - Meven, Martin
AU  - Roth, Georg
AU  - Kézsmárki, István
AU  - Murakawa, Hiroshi
AU  - Tokura, Yoshinori
AU  - Náfrádi, Bálint
TI  - The low-temperature crystal structure of the multiferroic melilite Ca$_{2}$ CoSi$_{2}$ O$_{7}$
JO  - Acta crystallographica / B
VL  - 72
IS  - 1
SN  - 2052-5206
CY  - Oxford [u.a.]
PB  - Wiley-Blackwell
M1  - FZJ-2016-06936
SP  - 126 - 132
PY  - 2016
AB  - In the antiferromagnetic ground state, below TN ≃ 5.7 K, Ca2CoSi2O7 exhibits strong magnetoelectric coupling. For a symmetry-consistent theoretical description of this multiferroic phase, precise knowledge of its crystal structure is a prerequisite. Here we report the results of single-crystal neutron diffraction on Ca2CoSi2O7 at temperatures between 10 and 250 K. The low-temperature structure at 10 K was refined assuming twinning in the orthorhombic space group P2(1)2(1)2 with a 3 × 3 × 1 supercell [a = 23.52 (1), b = 23.52 (1), c = 5.030 (3) Å] compared with the high-temperature normal state [tetragonal space group P42(1)m, a = b ≃ 7.86, c ≃ 5.03 Å]. The precise structural parameters of Ca2CoSi2O7 at 10 K are presented and compared with the literature X-ray diffraction results at 130 and 170 K (low-temperature commensurate phase), as well as at ∼ 500 K (high-temperature normal phase).
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000369393100014
C6  - pmid:26830804
DO  - DOI:10.1107/S2052520615023057
UR  - https://juser.fz-juelich.de/record/824327
ER  -