Jaynes information entropy of small molecules: Numerical evidence of the Collins conjecture

Collins's conjecture [Z. Naturforsch. 48A, 68 (1993)] that the correlation energy of a system is proportional to the Jaynes entropy [in Papers on Probability, Statistics and Statistical Physics, edited by R. Rosencrantz (Reidel, Dordrecht, 1983)] is investigated for small molecular systems. Numerical evidence supporting the conjecture is obtained by computing entropies from highly correlated configuration-interaction wave functions at various correlation levels, using sequences of increasingly larger basis sets. Further evidence is also obtained by examination of results obtained from a variety of correlation methods utilizing a fixed basis set.