Piezoelectricity in nominally centrosymmetric phases - Aktas, Oktay (Xi'an Jiaotong University. State Key Laboratory for Mechanical Behavior of Materials, Materials Science and Engineering) ; Kangama, Moussa (Xi'an Jiaotong University. State Key Laboratory for Mechanical Behavior of Materials, Materials Science and Engineering) ; Linyu, Gan (Xi'an Jiaotong University. State Key Laboratory for Mechanical Behavior of Materials, Materials Science and Engineering) ; Catalan, Gustau (Institut Català de Nanociència i Nanotecnologia) ; Ding, Xiangdong (Xi'an Jiaotong University. State Key Laboratory for Mechanical Behavior of Materials, Materials Science and Engineering) ; Zunger, Alex (University of Colorado. Energy Institute) ; Salje, Ekhard K. H. (University of Cambridge. Department of Earth Sciences)