Molecular modeling of the octacoordinated tetracarbonato-Nd(III), [Nd(CO3)(4)](5-), complex and its nonacoordinated fluoro- and aquo-adducts

作者：Sinha S P^*; Simas Alfredo M; Moura Gustavo L C

来源：Journal of Rare Earths, 2010, 28(6): 847-853.

DOI：10.1016/S1002-0721(09)60223-4

• lanthanides
• theoretical
• molecular models
• octacoordination
• carbonato complexes
• adducts
• MOPAC
• SPARKLE
• rare earths

Theoretical investigation on the structures of the octacoordinated [Nd(CO3)(4)](5-) and the nonacoordinated [Nd(CO3)(4 center dot)OH2](5-) complexes, using the SPARKLE parameters of the lanthanides within MOPAC, revealed that they possessed dodecahedral and square antiprismatic structures respectively with an average Nd-O distance of 0.249 nm. These structures and the Nd-O distances agreed well with those experimentally found in the crystal structures. Replacing the water molecule with a fluoride ion or a mondentatecarbonato ligand resulted in a nonacoordinated distorted square antiprismatic structures where the trans-carbonato groups were twisted. The corresponding decacoordinated structures with two fluoride ions or a bidentatecarbonato group, [Nd(CO3)(4)center dot F-2](7-) and [Nd(CO3)(5)](7-), were also investigated. In both cases considerable twisting of the transcarbonato groups was observed.

• 出版日期2010-12