Dipole oscillator strength properties and dispersion energies for CI₂

Dispersion-corrected Møller–Plesset second-order perturbation theory

“…17͒ basis sets, where the latter is a modified quadruple-zeta basis set designed for convergence of dispersion energy coefficients. [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] The latter values are accurate within 1%-2% as shown by comparison between different sets of experimental input data. 19,20 We obtain a mean absolute error of 18.1% for C 6 MP2 with the largest deviation of 76% for the interaction between two CS 2 molecules.…”

Dispersion without many-body density distortion: Assessment on atoms and small molecules

“…Dispersion coefficients were computed for four data sets: In all cases we compare our results with reference values obtained from dipole oscillator strength distribution (DOSD) data computed 14 or measured. 10,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]…”

“…max is a parameter, which is set equal to 22 in all our calculations, which yields in general reasonably converged results (see sec 3.5 for a more detailed discussion on convergence). We should remark that the choice of eq (22) is dictated mainly by the immediate availability of integrals with one-and two-electron reduced density matrices: our goal here is to investigate whether the methd is worth or not investing in further implementation and optimization. The question on how to determine the best…”

“…To compute the matrix elements of sec 2 we need the 1-RDM and 2-RDM of the monomers and the integrals of the functions b i (r) with the spatial orbitals, which, with the choice of eq (22), are all of the kind…”

Local random phase approximation with projected oscillator orbitals

“…The experimental dispersion coefficients have been determined from dipole oscillator strength distributions (DOSD) [59][60][61][62][63][64][65][66][67][68][69][70][71] Besides Eq. 32, the C 6 coefficients were also calculated from an iterative procedure, where the amplitude matrices T i j were updated according to the first two lines of Eq.…”