Jacob, FortunatusPogrebnoi, Alexander M.Pogrebnaya, Tatiana P.2024-06-172024-06-172016-07-16https://repository.udsm.ac.tz/handle/123456789/6082Different cluster ions detected earlier in saturated vapor over barium fluoride have been studied here the oretically. The equilibrium geometrical parameters and vibrational spectra were obtained for the ions BaF3 , Ba2F3+, Ba3F5+, Ba4F7+, and Ba5F9+ . The DFT/B3P86 and MP2 methods were implemented with theTZVP basis sets including the diffuse and polarized basis functions. Along with cluster ions, the dimer molecule Ba2F4 properties were examined; the existence of isomeric forms was confirmed and the rela tive concentration of the isomers was evaluated. The enthalpies of ion molecular reactions were obtained both theoretically and based on experimental data. The enthalpies of formation DfHo(0) of the specieswere determined (in kJ mol 1): 1356 ± 4 (BaF3 ); 1039 ± 12 (Ba2F3+); 2179 ± 16 (Ba3F5+); 3277 ± 35(Ba4F7+); 4316 ± 22 (Ba5F9+); 1859 ± 7 (Ba2F4).enBarium difluorideCluster ionsDFTMP2MP4Geometrical structureVibrational spectraEnthalpy of ion molecular reactionsEnthalpy of formationThermodynamic functionsJournal Articlehttps://doi.org/10.1016/j.comptc.2016.07.011.