To start assessing mechanochemical efficiency, we constrain our system to a constant total energy, U T : U T = C v T + n ∆U n , where increasing the internal strain of the molecule results in an equivalent temperature decrease. This 'cost function' can be arbitrarily changed to better represent a specific system or determine the efficiency (or cost ratio) of mechanochemistry in cases where the energy (or other costs) are derived differently. Under this cost function condition, with a known n f n (ϕ n , µ n , κ n ), we can more cleanly solve for the derivative, ∂k ∂µ , or more specifically ∂k ∂∆U with our known f n form.