Structure and bonding orientation of favorable growth unit Al6(OH)18(H2O)6 of gibbsite
(School of Chemistry and Chemical Engineering, Central South University,
Changsha 410083, China)
Changsha 410083, China)
Abstract: Three possible structures of the favorable growth unit Al6(OH)18(H2O)6 of gibbsite are calculated by ab initio at STO-3G, STO-3G*, STO-6G, STO-6G*, 3-21G, 6-31G levels and DFT at RB3LYP/3-21G, B3LYP/6-31G levels. The most excellent structure of Al6(OH)18(H2O)6 (structure [A]) is confirmed. Based on these calculation results and considering efficiency factor, ab initio at STO-3G level is selected to optimize the structure [A]. The calculation results are compared with the experimental structure parameters of correlative systems. The total energy, orbital population and atomic charge of structure [A] are calculated using Dipole & Sphere solvent model at 6-31G, B3LYP/6-31G, 6-31G*, B3LYP/6-31G*, 6-31G** and B3LYP/6-31G** levels. The bonding orientation of Al6(OH)18(H2O)6 is analyzed.
Key words: gibbsite; ab initio; density fuction theory(DFT); structure; orientation