The conformational analysis of bridged biphenyls and 2,2'-bipyridines has been undertaken with MM2-V4 force field (a modification of original MM2 force field containing the V4 torsional term). The known conformational properties of these compounds have been correctly reproduced. Ethano- and propano-bridged compounds have low interconversion barriers (ca. 4.5 and 10 kcal/mol, respectively), while butano-bridged derivatives present highly energetic barriers (ca. 25 kcal/mol). © 1990, American Chemical Society. All rights reserved.