摘要
基于晶体学结构,将化学键理论定量地应用到水合碳酸镁Mg5(CO3)4(OH)2·4H2O和MgCO3·3H2O的结晶行为研究中,以此指导和控制实际晶体的生长行为。根据所选晶面的化学键数目和强度,可以计算出该晶面的垂直生长速率,从而方便地预测出Mg5(CO3)4(OH)2·4H2O和MgCO3·3H2O晶体的理想形貌。Mg5(CO3)4(OH)2·4H2O晶体表现出六方片状的结晶习性,MgCO3·3H2O则具有六方柱的理想形貌。在实验中,六方片状的Mg5(CO3)4(OH)2·4H2O和MgCO3·3H2O六方柱可以通过简单的液相反应获得,证明我们的理论计算与实验结果完全相符。目前研究结果表明,单晶生长可以通过热力学意义上调整组成原子或离子的成键方式获得本质上的改进,这一过程为我们从动力学角度优化实验策略提供了更广阔的空间。
The chemical bonding theory is used to investigate the fundamental crystallization behaviours of magnesium carbonate hydrate crystals Mg5（CO3）4（OH）2·4H2O and MgCO3·3H2O in terms of crystallographic structure, with the aim to guide and control the practical crystal growth.The ideal morphology of Mg5（CO3）4（OH）2·4H2O and MgCO3·3H2O crystals has readily been predicted, by calculating the vertical growth rate of selected planes in terms of the bond number and bond strength. Theoretically, Mg5（CO3）4（OH）2·4H2O crystal exhibits hexagonal plate-shaped characteristics,while MgCO3·3H2O crystal possesses a hexagonal prism morphology.Experimentally,the hexagonal Mg5（CO3）4（OH）2·4H2O micro-platelets and MgCO3·3H2O micro-prisms with reproducible shape can be obtained by a simple liquid-phase reaction.Theoretical results are in a good agreement with our experimental observations. Single crystal growth can be improved by tuning the bonding modification of constituent atoms or ions, such a process can leave us a great space to kinetically maximize our experimental strategies.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2007年第5期991-999,共9页
Journal of Synthetic Crystals
基金
New Century Excellent Talents in University (No. NCET-05-0278)
the National Natural Science Foundation of China (No.20471012)
National Excellent Doctoral Dissertation of P.R.China (No.200322)
the Research Fund for the Doctoral Program of Higher Education(No.20040141004)
The Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education
关键词
化学键理论
晶体生长
结晶
水合碳酸镁
chemical bonding theory
crystal growth
crystallization
magnesium carbonate hydrates
