Snow crystals growing from water vapor occasionally exhibit morphologies with three-fold (trigonal) symmetry, even though the ice crystal lattice has a molecular structure with six-fold symmetry. In extreme cases, thin platelike snow crystals can grow into faceted forms that resemble simple equilateral triangles. Although far less common than hexagonal forms, trigonal snow crystals have long been observed both in nature and in laboratory studies, and their origin has been an enduring scientific puzzle. In this paper I describe how platelike trigonal structures can be grown on the ends of slender ice needles in air with high reliability at -14 C. I further suggest a physical model that describes how such structures can self-assemble and develop, facilitated by an edge-sharpening instability that turns on at a specific combination of temperature and water-vapor supersaturation. The results generally support a comprehensive model of structure-dependent attachment kinetics in ice growth that has been found to explain many of the overarching behaviors seen in the Nakaya diagram of snow crystal morphologies.
Observation of hexagonal close-packed water ice at conditions in ice giant planetary interiors
CEA DAM DIF（法国原子能委员会达姆-迪费中心）；Université Paris-Saclay, CEA, Laboratoire Matière en Conditions Extrêmes（巴黎萨克雷大学、法国原子能委员会极端条件物质实验室）；Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), Sorbonne Université, CNRS UMR 7590, MNHN（索邦大学矿物学、材料物理与宇宙化学研究所（IMPMC），CNRS UMR 7590，自然历史博物馆）；European Synchrotron Radiation Facility（欧洲同步辐射装置）
Sub-1-Angstrom-Resolution Imaging Reveals Phase Contrast Transition in Ice Ih Caused by Basal Stacking Faults
Pacific Northwest National Laboratory（太平洋西北国家实验室）；Argonne National Laboratory（阿贡国家实验室）；University of Washington（华盛顿大学）；University of Illinois, Chicago（伊利诺伊大学芝加哥分校）
From Stacking Disorder to Cubic Order: Ice Crystallization from Deeply Supercooled Water
Center for Nanoscale Materials, Argonne National Laboratory（阿贡国家实验室纳米材料中心）；Institute for Advanced Studies, College of Chemistry and Molecular Sciences, Wuhan University（武汉大学化学与分子科学学院高等研究院）；Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University（上海交通大学制冷与低温工程研究所）
Kinetics of Stacking Order Evolution During Heterogeneous Ice Formation
Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所，凝聚态物理国家实验室）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；Peking University（北京大学）
Crystallization of pristine cubic ice from liquid at ambient pressure
University College London（伦敦大学学院）；ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory（ISIS中子与μ子源，科学与技术设施委员会，拉瑟福德阿普尔顿实验室）；Uppsala Universitet（乌普萨拉大学）；University of Oxford（牛津大学）；The University of Manchester（曼彻斯特大学）
研究立方冰 Ic 能否从液态直接形成等问题，通过冷却介孔二氧化硅内水溶液在常压下获得原始立方冰 Ic，利用中子散射技术证明其可重复形成且为唯一稳定晶相，揭示该多晶型物在自然和合成过程中作用更重要。
A short-range metastable defect in the double layer ice
Institute of Atomic and Molecular Physics, Jilin University（吉林大学原子与分子物理研究所）；College of Physics, Jilin University（吉林大学物理学院）；International Center for Computational Methods and Software & State Key Lab of Superhard Materials, Changchun 130012, China（长春国际计算方法与软件中心及超硬材料国家重点实验室）；School of Electrical and Electronic Engineering, Nanyang TechnologicalUniversity（南洋理工大学电气与电子工程学院）
