J. Indian Chern. Soc., Vol. 88, December 2011, pp. 1817-1825 Synthesis, spectral characterization and single crystal X-ray diffraction study of arylazoimidazolium tetraiodobismuthate{III) compounds t D. Mallicka,#, K. K. Sarkera,$, R. Sahab and Chittaranjan Sinhaa* aoepartment of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata-700 032, India E-mail : c_r_sinha@yahoo.com bDepartment of Physics, Jadavpur University, Kolkata-700 032, India Manuscript received 24 October 2011, accepted 27 October 2011 Abstract : Eight new organic-inorganic hybrid compounds or 1,3-dialkyl-2-(arylazo)imidazolium, [RaaiR'R"] +, and [Bi 4 I 16 ]4- ion are synthesized. The structure has been established by spectral (FT-IR, UV-Vis, 1 H NMR) data and the structural conrirmation has been done by single crystal X-ray diffraction study in case or [Meaa1Me 2 + ] 4 [Bi 4 1 16 ] 4 - (\\here MeaaiMe2 + = 1,3-dimethyl-2-(p-tolylazo)lmidazolium). The DFT computation has been used to explain the electronic structure and the electronic spectra of the compounds. Keywords : Dialkyl-arylazoimidazolium salt, spectra, X-ray s1ructure, DFT computation. Introduction Organic-inorganic hybrid ionic compounds have at- tracted attention for their high mechanical and dimen- sional stability, high conductivity, large potential win- dow supporting electrolyte for fuel cells etc. 1 - 6 . Metal- halides of transition and nontransition metals have gener- ated halometallates, building agent to bring organic cat- ions together to develop sustainable hybrid materials 7 -9. Iodide W) has generated polymeric network with most of the metal ions and form myriad of bridged dimmers, cubanes, chains, strands, etc. 7 - 12 . TheN-heterocycle or- ganic cations like dialkyl imidazolium iodides are inter- esting class of ionic liquids with low vapor pressure and are important media for organic and inorganic compound synthesis and in separation processes 1 3-l5. Arylazo- imidazoles have given us a chance to synthesize good number of metal complexes 16 - 20 and also ionic compounds upon protonation or double alkylation 21 -25. Alkylation of arylazoimidazoles has synthesized 1 ,3-dialkyl-2- (arylazo)imidazolium salts of different anions like PF 6 - 21, Reo 4 - 22,23, cl-, [ZnC1 4 ] 2 -, 2 4 , [Pbi 3 -]n 25. Other groups of workers are also contributing to enrich this field with the studies of structural diversity of arylazoimidazolium ions with different oxo and nonoxo anions 26 · 27 . In this work we report arylazoimidazolium salts of iodobismuthate(III). The compounds are charac- terized by different spectroscopic studies and structural confirmation has been done in representative cases by single crystal X-ray diffraction measurements. Experimental materials 1,3-Dialkyl-2-(arylazo)imidazoles were prepared by the reported procedure 2 8. All other chemicals and sol- vents were reagent grade as received. Bismuth iodide was purchased from S. D. Fine Chemicals Co. Physical measurements Microanalytical data (C, H, N) were collected on Perkin-Elmer 2400 CHNS/0 elemental analyzer. Spec- troscopic data were obtained using the following instru- ments : UV-Vis spectra from Perkin-Elmer Lambda 25 spectrophotometer; IR spectra (KBr disk, 4000-450 cm- 1 ) from Perkin-Elmer RX-1 FTIR spectropl10tometer and 1 H NMR spectra from Bruker (AC) 300 MHz FTNMR spectrometer. Molar conductance was measured using Systronics-304 conductivity meter. tin Commemoration of the 150th Birth Anniversary of Acharya Prarulla Chandra Ray. Present address : 1 Department of Chemistry, Mrinalini Datta Mahavidyapith, Blrati, Kolkata-700 051, India. 5 Department of Chemistry, Mahadevananda Mahavidyalaya, Barrackpore, Monirampore, Kolkata-700 120, India. JICS-8 1817