| Abstract
| - 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 containingvarious anions such as CO32-, SO42-, OH-, F-, Cl-, Br-, and NO3-. We propose a modified force fieldof the cff91 form with the introduction of a double-well potential for describing oxygen−metal−oxygenangle bending. New parameters for describing the Ni−O bond and some refined nonbond parameters aresuggested. The structural parameters of β-Ni(OH)2, α-Ni(OH)2, and Ni/Al-LDHs obtained with themodified force field are in good agreement with experimental values. For NO3- and SO42- containedLDHs, the simulated results suggest several possible stacking modes of interlayer anions and watermolecules. The stability of dehydrated β-Ni(OH)2 has also been rationalized by the hydration energy ofβ-Ni(OH)2. The relative binding energies of interlayer anions in α-Ni(OH)2 and Ni/Al-LDHs decrease inthe order CO32-> SO42-> OH-> F-> Cl-> Br-> NO3-, which is consistent with the observedrelative ease of exchange of anions in the ion-exchange experiments employed for the synthesis of LDHs.
- Molecular dynamic (MD) simulations on β-Ni(OH)2, α-Ni(OH)2, and Ni/Al-layered double hydroxides (LDHs) have been performed for studying the structures and relative binding energies of them containing various anions, CO32-, SO42-, OH-, F-, Cl-, Br-, and NO3-.
|
