A joint experimental and theoretical approach is proposed for the conformational analysis of 2,2’-bithiophene in nonrigid media. Semiempirical calculations (AMPAC and INDO/S) are used to investigate the conformational structure of 2,2’-bithiophene. The geometry of the molecule is optimized by the AMPAC method using the AM1 (Austin model 1) Hamiltonian. It is shown that AMPAC predicts the final geometry (bond lengths and bond angles) relatively close to the experimental values reported for this molecule even though these geometrical parameters are better reproduced as expected at the ab initio level. The AMPAC and INDO/S methods are used to determine the torsional potential curve, within the rigid-rotor approximation, on the basis of the optimized geometry. The AMPAC calculations show two minima (theta = 150 degrees and theta = 30 degrees) and two maxima (theta = 90 degrees and theta = 0 degrees) reproducing the ab initio calculations. The absolute minimum is located at theta = 150 degrees, and the rotation barrier over the perpendicular conformation is calculated to be 0.46 kcal/mol. The energy difference between the two minima is calculated to be 0.25 kcal/mol. On the other hand, the torsional potential curve determined by the INDO/S method shows that the syn (theta = 0 degrees) and anti (theta = 180 degrees) conformers are quasi-isoenergetic and the most stabilized. The most destabilized conformation appears at theta = 90 degrees. But even if the small. details of the potential curve are not reproduced by INDO/S, the barrier for the syn-anti conversion is calculated to be 5.7 kcal/mol, and this compares very well with the rotation barrier determined experimentally by NMR measurements. Absorption spectra are obtained for 2,2’-bithiophene in the vapor phase, in a series of n-alkanes and in some solvents of various polarities.