A novel molecular tetravent ethyltriphenylphosphorous dibromide ((C6H5) 3PCH2Br2) has been synthesized in toluene and has been characterized by single crystal x-ray crystallography. Theoretical studies have been conducted utilizing DFT (B3LYP/6-311+ G (d, p) level of theory both in gas phase and solution using diverse solvents. Potential surface energy calculations revealed the existence of the tetravelent diionic form as a global minimum except in dimethylsolfoxide where our adduct is more stable. Calculations showed that the Br-Br bond distance is in quadratic variation with the medium dielectric constant. The unusual Br-Br lengthen is reasonably rationalized in terms of charge transfer of electron density from the π clouds in phenyl moieties to the σ* of the dibromine entity. The average harmonic oscillator index of aromaticity of the complex are found suffering a deviation from unity
