MRChem is a code for molecular electronic structure calculations, based on multiwavelet adaptive basis representation. We provide description of our implementation strategy and several benchmark calculations. Systems comprising more than thousand orbitals are investigated at the Hartree–Fock level theory, with an emphasis scaling properties. With design, terms that formally scale quadratically system size in effect have better because implicit screening introduced by inherent adaptivity...

New techniques in core–electron spectroscopy are necessary to resolve the structures of oxides f-elements and other strongly correlated materials that present only as powders not single crystals. Thus, accurate quantum chemical methods must be developed calculate core spectroscopic properties such materials. In this contribution, we an important development direction, extending our fully adaptive real-space multiwavelet basis framework tackle four-component Dirac-Coulomb-Breit Hamiltonian....

Wavelets and multiwavelets have lately been adopted in quantum chemistry to overcome challenges presented by the two main families of basis sets: Gaussian atomic orbitals plane waves. In addition their numerical advantages (high precision, locality, fast algorithms for operator application, linear scaling with respect system size, mention a few), they provide framework that narrows gap between theoretical formalism fundamental equations practical implementation working code. This realization...

We present a multiwavelet-based implementation of quantum/classical polarizable continuum model. The solvent model uses diffuse solute-solvent boundary and position-dependent permittivity, lifting the sharp-boundary assumption underlying many existing solvation models. are able to include both surface volume polarization effects in coupling, with guaranteed precision, due adaptive refinement strategies our multiwavelet implementation. can account for complex environments does not need...

Wavelets and Multiwavelets have lately been adopted in Quantum Chemistry to overcome challenges presented by the two main families of basis sets: Gaussian atomic orbitals plane waves. In addition their numerical advantages (high precision, locality, fast algorithms for operator application, linear scaling with respect system size, mention a few) they provide framework which narrows gap between theoretical formalism fundamental equations practical implementation working code. This realization...

Abstract We have implemented a self-consistent field solver for Hartree–Fock calculations, by making use of Multiwavelets and Multiresolution Analysis. show how such is inherently preconditioned steepest descent method therefore good starting point rapid convergence. A distinctive feature our implementation the absence any reference to kinetic energy operator. This desirable when are employed, because differential operators as Laplacian in challenging represent correctly. The theoretical...

Abstract New techniques in core-electron spectroscopy are necessary to solve the structures of oxides f -elements and other stronglycorrelated materials that present only as powders not single crystals. Thus, more accurate quantum chemicalmethods need be developed calculate core spectroscopic properties such materials. Here, we have presented firstdevelopment a direction, extending fully adaptive real-space multiwavelet basis 4-component Dirac-Coulomb-BreitHamiltonian. Multiwavelets were...

New techniques in core-electron spectroscopy are necessary to resolve the structures of oxides $f$-elements and other strongly correlated materials that present only as powders not single crystals. Thus, accurate quantum chemical methods need be developed calculate core spectroscopic properties such materials. In this contribution, we an important development direction, extending our fully adaptive real-space multiwavelet basis framework tackle 4-component Dirac-Coulomb-Breit Hamiltonian. We...

Abstract New techniques in core-electron spectroscopy are necessary to resolve the structures of oxides f -elements and other strongly correlated materials that present only as powders not single crystals. Thus, accurate quantum chemical methods need be developed calculate core spectroscopic properties such materials. In this contribution, we an important development direction, extending our fully adaptive real-space multiwavelet basis framework tackle 4-component Dirac-Coulomb-Breit...

MRChem is a code for molecular electronic structure calculations, based on multiwavelet adaptive basis representation. We provide description of our implementation strategy and several benchmark calculations. Systems comprising more than thousand orbitals are investigated at the HF level theory, with an emphasis scaling properties. With design, terms which formally scale quadratically system size, in effect have better because implicit screening introduced by inherent adaptivity method: all...

We present a multiwavelet-based implementation of quantum/classical polarizable continuum model. The solvent model uses diffuse solute-solvent boundary and position-dependent permittivity, lifting the sharp-boundary assumption underlying many existing solvation models. are able to include both surface volume polarization effects in coupling, with guaranteed precision, due adaptive refinement strategies our multiwavelet implementation. can account for complex environments does not need...