TY - JOUR
T1 - An Unusual Phase Transition Driven by Vibrational Entropy Changes in a Hybrid Organic–Inorganic Perovskite
AU - Wei, Wenjuan
AU - Li, Wei
AU - Butler, Keith T.
AU - Feng, Guoqiang
AU - Howard, Christopher J.
AU - Carpenter, Michael A.
AU - Lu, Peixiang
AU - Walsh, Aron
AU - Cheetham, Anthony K.
N1 - Funding Information:
The authors acknowledge the funding support from the National Natural Science Foundation of China (Grant no. 21571072). W.W., G.F., W.L. and P.L. thank the Fundamental Research Funds for the Central Universities, HUST (Grant no. 2017KFXKJC002). W.L. is grateful to Prof. Song Gao for his illuminating suggestions.
Funding Information:
The authors acknowledge the funding support from the National Natural Science Foundation of China (Grant no.
Funding Information:
21571072). W.W., G.F., W.L. and P.L. thank the Fundamental Research Funds for the Central Universities, HUST (Grant no. 2017KFXKJC002). W.L. is grateful to Prof. Song Gao for his illuminating suggestions.
Publisher Copyright:
© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2018/7/16
Y1 - 2018/7/16
N2 - The driving forces for the phase transitions of ABX3 hybrid organic–inorganic perovskites have been limited to the octahedral tilting, order–disorder, and displacement. Now, a complex structural phase transition has been explored in a HOIP, [CH3NH3][Mn(N3)3], based on structural characterizations and ab initio lattice dynamics calculations. This unusual first-order phase transition between two ordered phases at about 265 K is primarily driven by changes in the collective atomic vibrations of the whole lattice, along with concurrent molecular displacements and an unusual octahedral tilting. A significant entropy difference (4.35 J K−1 mol−1) is observed between the low- and high-temperature structures induced by such atomic vibrations, which plays a main role in driving the transition. This finding offers an alternative pathway for designing new ferroic phase transitions and related physical properties in HOIPs and other hybrid crystals.
AB - The driving forces for the phase transitions of ABX3 hybrid organic–inorganic perovskites have been limited to the octahedral tilting, order–disorder, and displacement. Now, a complex structural phase transition has been explored in a HOIP, [CH3NH3][Mn(N3)3], based on structural characterizations and ab initio lattice dynamics calculations. This unusual first-order phase transition between two ordered phases at about 265 K is primarily driven by changes in the collective atomic vibrations of the whole lattice, along with concurrent molecular displacements and an unusual octahedral tilting. A significant entropy difference (4.35 J K−1 mol−1) is observed between the low- and high-temperature structures induced by such atomic vibrations, which plays a main role in driving the transition. This finding offers an alternative pathway for designing new ferroic phase transitions and related physical properties in HOIPs and other hybrid crystals.
KW - ab initio lattice dynamics calculations
KW - hybrid organic–inorganic perovskites
KW - phase transitions
KW - vibrational entropy
UR - http://www.scopus.com/inward/record.url?scp=85049795082&partnerID=8YFLogxK
U2 - 10.1002/anie.201803176
DO - 10.1002/anie.201803176
M3 - Article
C2 - 29845741
AN - SCOPUS:85049795082
SN - 1433-7851
VL - 57
SP - 8932
EP - 8936
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
IS - 29
ER -