I like to draw a molecule in different conformations in a) website or b) freeware and
Calculate its relative energy difference (for example to the lowest global energy conformation)
Display the lowest energy conformation
I'm particularly interested in the calculation of diaxial interactions, gauche interactions, double gauche pentane interactions (and less in ring strain, like chair / half-chair / twisted rings).
I know there are plenty of tools for modelling conformational and electrostacic properties. Most of those are not freely available. Do you an easy solution? It does not must to be the most precise one, relative energy differences in steps of 0.1 kcal/mol between two drawn conformations would be fine for me.
May be this question is off-topic, because it's a software request, but I didn't know where else I could ask this question.