sp<sup>2</sup> to sp<sup>3</sup> Hybridization Transformation in Ionic Crystals under Unprecedentedly Low Pressure
Xingxing Jiang, Мaxim S. Моlokeev, Naizheng Wang, Yonggang Wang, Ting Bin Wen, Zhichao Dong, Youquan Liu, Wei Li, Zheshuai Lin
Abstract
Abstract Under cold pressure sp 1 /sp 2 ‐to‐sp 3 hybridization transformation has been exclusively observed in covalent or molecular crystals overwhelmingly above ≈10 GPa, and the approaches to lower the transition pressure are limited on external heat‐treatment and/or catalyzers. Herein we demonstrate that, by internal‐lattice stress‐transfer from ionic to covalent groups, the transformation can be significantly prompted, as shown in a crystal of LiBO 2 under 2.85 GPa for the first case in ionic crystals. This unprecedentedly low transformation pressure is ascribed to the enhanced localized stress on covalent B−O frames transferred from ionic Li−O bonds in LiBO 2 , and accordingly the corresponding structural feature is summarized. This work provides an internal structural regulation strategy for pressure‐reduction of the s‐p orbital hybridization transformation and extends the sp 1 /sp 2 ‐to‐sp 3 transformation landscape from molecular and covalent compounds to ionic systems.