Computation of NMR shieldings at the CASSCF level using gauge-including atomic orbitals and Cholesky decomposition
Tommaso Nottoli, Sophia Burger, Stella Stopkowicz, Gauss J., Filippo Lipparini
Abstract
We present an implementation of coupled-perturbed complete active space self-consistent field (CP-CASSCF) theory for the computation of nuclear magnetic resonance chemical shifts using gauge-including atomic orbitals and Cholesky decomposed two-electron integrals. The CP-CASSCF equations are solved using a direct algorithm where the magnetic Hessian matrix-vector product is expressed in terms of one-index transformed quantities. Numerical tests on systems with up to about 1300 basis functions provide information regarding both the computational efficiency and limitations of our implementation.
Topics & Concepts
Cholesky decompositionAtomic orbitalComputationComputational chemistryDecompositionPhysicsChemistryComputer scienceQuantum mechanicsAlgorithmOrganic chemistryElectronEigenvalues and eigenvectorsAdvanced NMR Techniques and ApplicationsAdvanced Chemical Physics StudiesRadioactive element chemistry and processing