Complex Cs(ATZ) was prepared by mixing aqueous solution of CsOH and 5-aminotetrazole (ATZ). The crystal structure of Cs(ATZ) was determined by X-ray diffraction analysis. The crystal is orthorhombic with space group Pnma and unit-cell parameters of a＝0.8114(4) nm, b＝0.6907(4) nm, c＝0.9122(5) nm, V＝0.5113(5) nm³, D_c＝2.819 g/cm³, Z＝4, F(000)＝392, μ＝7.112 mm^－1, R＝0.0485. Cs^＋ is 9-coordinated with N atoms. 3-D framework structure was formed by hydrogen bonds, bridging between metal cations with N atoms and intermolecular forces. Cs(ATZ) was also characterized by IR and Raman spectroscopy. From measurements of the reaction enthalpy and solution enthalpy of ATZ and Cs(ATZ) in CsOH aqueous solution, the standard enthalpy of formation of the complex was calculated as (－430.56±0.43) kJ•mol^－1.

Key words: ATZ, Cs(ATZ), crystal structure, preparation, standard enthalpy of formation