TY - JOUR
T1 - The X40×10 Halogen Bonding Benchmark Revisited: Surprising Importance of (n–1)d Subvalence Correlation
T2 - Surprising Importance of (n-1)d Subvalence Correlation
AU - Kesharwani, Manoj K.
AU - Manna, Debashree
AU - Sylvetsky, Nitai
AU - Martin, Jan M. L.
PY - 2018/3/1
Y1 - 2018/3/1
N2 - We have re-evaluated the X40×10 benchmark for halogen bonding using conventional and explicitly correlated coupled cluster methods. For the aromatic dimers at small separation, improved CCSD(T)-MP2 "high-level corrections" (HLCs) cause substantial reductions in the dissociation energy. For the bromine and iodine species, (n-1)d subvalence correlation increases dissociation energies and turns out to be more important for noncovalent interactions than is generally realized; (n-1)sp subvalence correlation is much less important. The (n-1)d subvalence term is dominated by core-valence correlation; with the smaller cc-pVDZ-F12-PP and cc-pVTZ-F12-PP basis sets, basis set convergence for the core-core contribution becomes sufficiently erratic that it may compromise results overall. The two factors conspire to generate discrepancies of up to 0.9 kcal/mol (0.16 kcal/mol RMS) between the original X40×10 data and the present revision.
AB - We have re-evaluated the X40×10 benchmark for halogen bonding using conventional and explicitly correlated coupled cluster methods. For the aromatic dimers at small separation, improved CCSD(T)-MP2 "high-level corrections" (HLCs) cause substantial reductions in the dissociation energy. For the bromine and iodine species, (n-1)d subvalence correlation increases dissociation energies and turns out to be more important for noncovalent interactions than is generally realized; (n-1)sp subvalence correlation is much less important. The (n-1)d subvalence term is dominated by core-valence correlation; with the smaller cc-pVDZ-F12-PP and cc-pVTZ-F12-PP basis sets, basis set convergence for the core-core contribution becomes sufficiently erratic that it may compromise results overall. The two factors conspire to generate discrepancies of up to 0.9 kcal/mol (0.16 kcal/mol RMS) between the original X40×10 data and the present revision.
U2 - https://doi.org/10.1021/acs.jpca.7b10958
DO - https://doi.org/10.1021/acs.jpca.7b10958
M3 - مقالة
SN - 1089-5639
VL - 122
SP - 2184
EP - 2197
JO - The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory
JF - The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory
IS - 8
ER -