The effect of guest molecules on the conformation and molecular assembly of the fac-[RuCl3(NO)(dppb)] complex

This paper describes the occurrence of two crystalline solvate forms of the nitrosyl ruthenium complex fac-[RuCl3(NO)(dppb)] (dppb = 1,4-bis(diphenylphosphino)butane), and the role of acetone and chloroform inclusions on molecular conformations and molecular assemblies. These two crystal forms were identified by X-ray diffraction and infrared spectroscopy, and compared with the known crystal structure of the complex, without the solvent. Using the FT-IR technique, it was possible to assign the bands characteristics of the nitrosyl stretching and the solvents. An interesting structural aspect occurring in both solvate forms is that the solvent inclusion modifies the molecular conformation of the dppb ligand and the molecular assembly. Due to the similar total volume of guest solvents, the unit cell parameters are similar, resulting in an isostructural arrangement with small differences in the intermolecular interactions, with caged guest solvents, that interact with the complex by hydrogen bonds.