90 citations · 218 across the 17 of their papers we have counts for
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Use of Cholesky decomposition in the CFOUR program package
Jürgen Gauss, Simon Blaschke, Sophia Burger +10
An overview is given about our efforts to speed up high-level computations of molec- ular energies and properties using Cholesky decomposition (CD). We describe the cor- responding…
Exploitation of complex Abelian point groups in quantum-chemical calculations
Marios-Petros Kitsaras, Stella Stopkowicz
Quantum-chemical calculations often make use of point-group theory to exploit molecular symmetry, resulting in a reduction of the computational cost and in insights into the electr…
Unitary Coupled-Cluster theory for the treatment of molecules in strong magnetic fields
Laura Grazioli, Marios-Petros Kitsaras, Stella Stopkowicz
In Coupled-Cluster (CC) theory, unphysical complex energies may arise in the presence of strong magnetic fields, near conical intersections, or in systems exhibiting complex Abelia…
Equation-of-motion coupled-cluster variants in combination with perturbative triples corrections in strong magnetic fields
Marios-Petros Kitsaras, Florian Hampe, Lena Reimund +1
In this paper, we report on the implementation of the EOM spin-flip (SF), ionization-potential (IP) and electron-affinity (EA) coupled cluster singles doubles (CCSD) methods for at…
Cholesky Decomposition and the Second-Derivative Two-Electron Integrals Required for the Computation of Magnetizabilities using Gauge-Including Atomic Orbitals
Sophia Burger, Stella Stopkowicz, Jürgen Gauss
The computation of magnetizability tensors using gauge-including atomic orbitals is discussed in the context of Cholesky decomposition for the two-electron repulsion integrals with…
Finite-Field Cholesky Decomposed Coupled-Cluster Techniques (ff-CD-CC): Theory and Application to Pressure Broadening of Mg by a He Atmosphere and a Strong Magnetic Field
Simon Blaschke, Marios-Petros Kitsaras, Stella Stopkowicz
For the interpretation of spectra of magnetic stellar objects such as magnetic white dwarfs (WDs) highly accurate quantum chemical predictions for atoms and molecules in finite mag…
Diagrams and symmetry in polaritonic coupled cluster theory
Laurenz Monzel, Stella Stopkowicz
We present a diagrammatic notation to derive the quantum-electrodynamic coupled cluster (QED-CC) equations needed for the description for polaritonic ground and excited states. Our…
The approximate Coupled-Cluster methods CC2 and CC3 in a finite magnetic field
Marios-Petros Kitsaras, Laura Grazioli, Stella Stopkowicz
In this paper, we report on the implementation of CC2 and CC3 in the context of molecules in finite magnetic fields. The methods are applied to the investigation of atoms and molec…
A Cholesky decomposition-based implementation of relativistic two-component coupled-cluster methods for medium-sized molecules
Chaoqun Zhang, Filippo Lipparini, Stella Stopkowicz +2
A Cholesky decomposition (CD)-based implementation of relativistic two-component coupled-cluster (CC) and equation-of-motion CC (EOM-CC) methods using an exact two-component Hamilt…
Magnetic Optical Rotation from Real-Time Simulations in Finite Magnetic Fields
Benedicte Sverdrup Ofstad, Meilani Wibowo-Teale, Håkon Emil Kristiansen +8
We present a numerical approach to magnetic optical rotation based on real-time time-dependent electronic-structure theory. Not relying on perturbation expansions in the magnetic-f…
Computation of NMR shieldings at the CASSCF level using gauge-including atomic orbitals and Cholesky decomposition
Tommaso Nottoli, Sophia Burger, Stella Stopkowicz +2
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 u…
Cholesky decomposition of two-electron integrals in quantum-chemical calculations with perturbative or finite magnetic fields using gauge-including atomic orbitals
Jürgen Gauss, Simon Blaschke, Sophia Burger +3
A rigorous analysis is carried out concerning the use of Cholesky decomposition (CD) of two-electron integrals in the case of quantum-chemical calculations with finite or perturbat…
Cholesky decomposition of complex two-electron integrals over GIAOs: Efficient MP2 computations for large molecules in strong magnetic fields
Simon Blaschke, Stella Stopkowicz
In large-scale quantum-chemical calculations the electron-repulsion integral (ERI) tensor rapidly becomes the bottleneck in terms of memory and disk space. When an external finite…
NMR Chemical Shift Computations at Second-Order Møller-Plesset Perturbation Theory Using Gauge-Including Atomic Orbitals and Cholesky-Decomposed Two-Electron Integrals
Sophia Burger, Filippo Lipparini, Jürgen Gauss +1
We report on a formulation and implementation of a scheme to compute NMR shieldings at second-order Moller-Plesset (MP2) perturbation theory using gauge-including atomic orbitals (…
Complex Ground-State and Excitation Energies in Coupled-Cluster Theory
Simon Thomas, Florian Hampe, Stella Stopkowicz +1
Since in coupled-cluster (CC) theory ground-state and excitation energies are eigenvalues of a non-Hermitian matrix, these energies can in principle take on complex values. In this…
Current Density-Functional Theory using meta-Generalized Gradient Exchange--Correlation Functionals
James W. Furness, Joachim Verbeke, Erik I. Tellgren +4
We present the self-consistent implementation of current-dependent (hybrid) meta generalized gradient approximation (mGGA) density functionals using London atomic orbitals. A previ…
Coupled-cluster theory for atoms and molecules in strong magnetic fields
Stella Stopkowicz, Jürgen Gauss, Kai K. Lange +2
An implementation of coupled-cluster (CC) theory to treat atoms and molecules in finite magnetic fields is presented. The main challenges stem from the magnetic-field dependence in…