Comparison of Morokuma and perturbation theory approaches to decomposition of interaction energy. (NH4)+…NH3

Abstract The interaction energy between NH 4 + and NH 3 is decomposed for a range of intermolecular separations within the context of a variety of basis sets including 6-31G ** , 6-31+G ** , and Sadlej polarization sets of type [5s3p2d/3s2p], including a set of f-functions as well. The electrostatic component dominates the interaction in all cases. At separations near the minimum or closer, the Morokuma second-order components (POL and CT) blow up. In contrast, Δ E SCF def , representing mutual polarization and orbital relaxation, is in good agreement with the induction energy computed via perturbation theory. Correction of the superposition error is noted to be important for this agreement and, indeed, for all components. In fact, following this correction, even the smaller sets provide accurate measures of the exchange term. The second-order correlation correction to the electrostatic interaction ϵ es 12 is computed and found to be fairly small. The dispersion energy embodied in ϵ disp 20 is considerably larger than the latter term and grows in proportion to the flexibility of the basis set.

[1]  S. Scheiner,et al.  Nonadditive effects in HF and HCl trimers , 1989 .

[2]  B. Roos,et al.  Polarized basis sets for accurate predictions of molecular electric properties. Electric moments of the LiH molecule , 1985 .

[3]  M. Randic,et al.  The theory of intermolecular forces in the region of small orbital overlap , 1965, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[4]  Keiji Morokuma,et al.  Molecular Orbital Studies of Hydrogen Bonds. III. C=O···H–O Hydrogen Bond in H2CO···H2O and H2CO···2H2O , 1971 .

[5]  Kazuo Kitaura,et al.  A new energy decomposition scheme for molecular interactions within the Hartree‐Fock approximation , 1976 .

[6]  S. Scheiner,et al.  Analysis of the potential energy surface of Ar–NH3 , 1989 .

[7]  P. Fowler,et al.  The long range model of intermolecular forces , 1983 .

[8]  V. Kellö,et al.  Medium-size polarized basis sets for high-level-correlated calculations of molecular electric properties , 1991 .

[9]  J. Chandrasekhar,et al.  Efficient and accurate calculation of anion proton affinities , 1981 .

[10]  Ernest R. Davidson,et al.  Energy partitioning of the self‐consistent field interaction energy of ScCO , 1989 .

[11]  B. Jeziorski,et al.  Variation-perturbation treatment of the hydrogen bond between water molecules , 1976 .

[12]  L. Piela,et al.  First-order perturbation treatment of the short-range repulsion in a system of many closed-shell atoms or molecules , 1976 .

[13]  A. J. Sadlej.  Long range induction and dispersion interactions between Hartree-Fock subsystems , 1980 .

[14]  C. Ghio,et al.  Noncovalent interactions of medium strength. A revised interpretation and examples of its applications , 1989 .

[15]  P. C. Hariharan,et al.  The influence of polarization functions on molecular orbital hydrogenation energies , 1973 .

[16]  B. Jeziorski,et al.  Exchange polarization effects in the interaction of closed-shell systems , 1977 .

[17]  W. Sokalski,et al.  Basis set extension effects on the He2 interaction energy components , 1987 .

[18]  C. Ghio,et al.  Effect of counterpoise corrections on the components of the interaction energy in the formate-, acetate-, and phosphate-water dimers: a study of basis set effects , 1989 .

[19]  P. Dacre.  A calculation of the helium pair polarizability including correlation effects , 1978 .

[20]  G. Chałasiński.  Perturbation calculations of the interaction energy between closed-shell Hartree-Fock atoms , 1983 .

[21]  L. Piela,et al.  Proper correction for the basis set superposition error in SCF calculations of intermolecular interactions , 1987 .

[22]  S. Scheiner,et al.  Primary and secondary basis set superposition error at the SCF and MP2 levels. H3N‐‐Li+ and H2O‐‐Li+ , 1987 .

[23]  Keiji Morokuma,et al.  Why do molecules interact? The origin of electron donor-acceptor complexes, hydrogen bonding and proton affinity , 1977 .

[24]  S. Scheiner,et al.  Accurate Evaluation of SCF and MP2 Components of Interaction Energies. Complexes of HF, OH2 and NH3 with Li+ , 1988 .

[25]  S. F. Boys,et al.  The calculation of small molecular interactions by the differences of separate total energies. Some procedures with reduced errors , 1970 .

[26]  B. Roos,et al.  An ab initio study of the non-linear optical properties of the He atom and the H2 molecule , 1984 .

[27]  L. Piela,et al.  Interpretation of the Hartree-Fock interaction energy between closed-shell systems , 1988 .

[28]  G. Karlström,et al.  Basis set superposition effects on properties of interacting systems. Dipole moments and polarizabilities , 1982 .