For the sake of simplicity we use the united atom (UA) Optimized Potentials for Liquid Simulations (OPLS) model to describe the conformational potential energy landscape V of branched alkanes (ignoring non-bonded intramolecular interactions and with fixed C-C distances). We denote each building block energy function g w-x-y-z : S 1 → R with the subscript w-x-y-z, where each variable (w, x, y, and z) is the degree of the carbon (number of C-C bonds attached to it), and x-y is the internal bond (rotational axis of the dihedral angles present). Accounting for symmetry, there are 78 possible w-x-y-z where w, z ∈ {1, 2, 3, 4} and x, y ∈ {2, 3, 4}. To reduce combinatorial complexity (without loss of generality of the methodology), we focus on building blocks of type 1-x-y-1 that form the molecular sub-units of the larger branched alkanes studied (Figure ).