Principal component analysis of theoretical data [B3LYP/6-311 + g(d,p)] may predict the main interactions governing the conformational equilibrium of a series of trans-2-substituted methoxycyclohexanes. The classical syn-1,3-diaxial repulsion, as well as the 'gauche effect' for some substituents, explain the preference towards the eq-eq conformation, although dipolar and steric repulsions between the eq-eq substituents is also an important intramolecular interaction present in these systems favouring the ax-ax form. The intramolecular interactions were supported by theoretical variables, such as nuclear repulsion energy, hardness, charges and bond order (obtained from the density matrix of the theoretical calculations), which led to the conformers separation into ax-ax and eq-eq classes. (C) 2002 Elsevier Science B.V. All rights reserved.6183219224