Molecular Dynamics Modeling of the Structures and Binding Energies of α-Nickel Hydroxides and Nickel−Aluminum Layered Double Hydroxides Containing Various Interlayer Guest Anions
Molecular Dynamics Modeling of the Structures and Binding Energies of α-Nickel Hydroxides and Nickel−Aluminum Layered Double Hydroxides Containing Various Interlayer Guest Anions
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DOI：
10.1021/cm060867h
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发表时间：
2006-08
影响因子：
8.6
通讯作者：
Hui Li and;Jing Ma;D. Evans;T. Zhou;and Feng Li;X. Duan
中科院分区：
文献类型：
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作者：
Hui Li and;Jing Ma;D. Evans;T. Zhou;and Feng Li;X. Duan
采用分子动力学（MD）方法对β-Ni（OH）2、α-Ni（OH）2和Ni/Al层状双氢氧化物（LDHs）进行了模拟，研究了含CO 32-、SO 42-、OH-、F-、Cl-、Br-和NO3-等阴离子材料的结构和结合能.我们提出了一个修正的力场的cff 91形式，引入了一个双阱势来描述氧-金属-氧角弯曲。提出了描述Ni-O键的新参数和一些精细的非键参数。用改进的力场法计算得到的β-Ni（OH）2、α-Ni（OH）2和Ni/Al-LDHs的结构参数与实验值吻合较好。对于含NO3-和SO 42-的LDHs，模拟结果表明了层间阴离子和水分子的几种可能的堆积模式。脱水β-Ni（OH）2的稳定性也被β-Ni（OH）2的水化能合理化。α-Ni（OH）2和Ni/Al-LDHs层间阴离子的相对结合能均按CO 32- > SO2- > SO2-的顺序减小。
Molecular dynamics (MD) simulations of β-Ni(OH)2, α-Ni(OH)2, and Ni/Al-layered double hydroxides (LDHs) have been performed in order to study structures and binding energies of the materials containing various anions such as CO32-, SO42-, OH-, F-, Cl-, Br-, and NO3-. We propose a modified force field of the cff91 form with the introduction of a double-well potential for describing oxygen−metal−oxygen angle bending. New parameters for describing the Ni−O bond and some refined nonbond parameters are suggested. The structural parameters of β-Ni(OH)2, α-Ni(OH)2, and Ni/Al-LDHs obtained with the modified force field are in good agreement with experimental values. For NO3- and SO42- contained LDHs, the simulated results suggest several possible stacking modes of interlayer anions and water molecules. The stability of dehydrated β-Ni(OH)2 has also been rationalized by the hydration energy of β-Ni(OH)2. The relative binding energies of interlayer anions in α-Ni(OH)2 and Ni/Al-LDHs decrease in the order CO32- > SO...