Dimer form of 1,3-dimethyluracil studied by the AM1 semiempirical method

A study of the dimer form of 1,3-dimethyluracil was carried out. The optimum geometric parameters in the monomeric and dimeric forms were obtained using the AM 1 semiempirical method. The results were compared with those reported by X-ray diffraction. The energies in the dimer formation and in the intramolecular C? H···O interaction were calculated. Electronic density maps in two and three dimensions were drawn. Several calculated thermodynamic parameters are discussed. © 1994 John Wiley & Sons, Inc.