Comprehensive Investigation of Geometrical and Electronic Structure In Ground As Well As the First Excited State of 3, 4-Difluoroaniline (C6h5nf2) Was Carried Out. the Experimentally Observed Spectral Data (Ft-Ir and Ft-Raman) of the Title Compound Was Compared With the Spectral Data Obtained By Electronic Structures Calculations, at the Rhf/6-31G* and B3lyp/6-31G* Basis Set Has Been Carried Out. the Molecular Optimized Geometry Parameter Like Bond Angle, Bond Length, Stretching and Bending Force Constants of Title Molecule Were Calculated.