TY - JOUR
T1 - Space group determination and first-principles structure optimization of the A -site ordered perovskite-type manganite NdBaMn2 O6
AU - Islam, Md Shafiqul
AU - Morikawa, Daisuke
AU - Yamada, Shigeki
AU - Aryal, Bikas
AU - Tsuda, Kenji
AU - Terauchi, Masami
N1 - Funding Information:
The authors would like to thank Dr. Yohei Sato for the valuable discussions and Mr. Masaki Ageishi for his careful maintenance of the JEM-2010FEF transmission electron microscopes. M.S.I. acknowledges financial support through a MEXT scholarship. This work is partly supported by JSPS KAKENHI Grants No. JP20H05176 and No. JP18H03674.
Publisher Copyright:
© 2022 American Physical Society.
PY - 2022/5/1
Y1 - 2022/5/1
N2 - Space groups and crystal structures of A-site ordered NdBaMn2O6 perovskite have been investigated by a combination of selected-area electron diffraction (SAED), convergent-beam electron diffraction (CBED), and first-principles methods at high-temperature (HT ≈ 450 K), room-temperature (RT ≈ 293 K), and low-temperature (LT ≈ 95 K) phases. By symmetry analysis of the CBED patterns, space groups of NdBaMn2O6 at HT, RT, and LT phases have been determined to be P4/mmm (No. 123), C2mm (No. 38), and P21am (No. 26), respectively. The space groups and the optimized structures using first-principle calculations at the HT and RT phases allow a single crystallographic site for Mn atoms, indicating no charge ordering state. At the LT phase, the observed SAED and CBED patterns revealed the existence of fourfold periodicity along the c axis compared with the pseudocubic unit cell. The optimized structure of the LT phase suggested four inequivalent Mn sites classified into two crystallographically different MnO2 layers. Moreover, the structure showed that the four distinct MnO6 octahedra are similarly compressed in the apical direction.
AB - Space groups and crystal structures of A-site ordered NdBaMn2O6 perovskite have been investigated by a combination of selected-area electron diffraction (SAED), convergent-beam electron diffraction (CBED), and first-principles methods at high-temperature (HT ≈ 450 K), room-temperature (RT ≈ 293 K), and low-temperature (LT ≈ 95 K) phases. By symmetry analysis of the CBED patterns, space groups of NdBaMn2O6 at HT, RT, and LT phases have been determined to be P4/mmm (No. 123), C2mm (No. 38), and P21am (No. 26), respectively. The space groups and the optimized structures using first-principle calculations at the HT and RT phases allow a single crystallographic site for Mn atoms, indicating no charge ordering state. At the LT phase, the observed SAED and CBED patterns revealed the existence of fourfold periodicity along the c axis compared with the pseudocubic unit cell. The optimized structure of the LT phase suggested four inequivalent Mn sites classified into two crystallographically different MnO2 layers. Moreover, the structure showed that the four distinct MnO6 octahedra are similarly compressed in the apical direction.
UR - http://www.scopus.com/inward/record.url?scp=85131294186&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.105.174114
DO - 10.1103/PhysRevB.105.174114
M3 - Article
AN - SCOPUS:85131294186
SN - 2469-9950
VL - 105
JO - Physical Review B
JF - Physical Review B
IS - 17
M1 - 174114
ER -