101 citations · 215 across the 12 of their papers we have counts for
12 papers
Variational Density Functional Calculations of Excited States: Conical Intersection and Avoided Crossing in Ethylene Bond Twisting
Yorick L. A. Schmerwitz, Aleksei V. Ivanov, Elvar Ö. Jónsson +2
Theoretical studies of photochemical processes require a description of the energy surfaces of excited electronic states, especially near degeneracies, where transitions between st…
Assessment of the Accuracy of Density Functionals for Calculating Oxygen Reduction Reaction on Nitrogen Doped Graphene
Björn Kirchhoff, Aleksei Ivanov, Egill Skúlason +3
Experimental studies of the oxygen reduction reaction (ORR) at nitrogen doped graphene electrodes have reported a remarkably low overpotential, on the order of 0.5 V, similar to Pt…
Chemical bonding theories as guides for self-interaction corrected solutions: multiple local minima and symmetry breaking
Kai Trepte, Sebastian Schwalbe, Simon Liebing +5
Fermi--Löwdin orbitals (FLO) are a special set of localized orbitals, which have become commonly used in combination with the Perdew--Zunger self-interaction correction (SIC) in th…
Partial Meissner effect measurement by a superconducting magnetic flux lens
A. Ivanov, T. Koettig, A. Macpherson
Magnetic flux trapping in the Meissner transition of superconducting radio frequency cavities can substantially increase dissipation which impacts cryogenic costs and necessitates…
Method for Calculating Excited Electronic States Using Density Functionals and Direct Orbital Optimization with Real Space Grid or Plane Wave Basis Set
Aleksei V. Ivanov, Gianluca Levi, Elvar Ö. Jónsson +1
A direct orbital optimization method is presented for density functional calculations of excited electronic states using either a real space grid or a plane wave basis set. The met…
Mn Dimer can be Described Accurately with Density Functional Calculations when Self-interaction Correction is Applied
Aleksei V. Ivanov, Tushar K. Ghosh, Elvar Ö. Jónsson +1
Qualitatively incorrect results are obtained for the Mn dimer in density functional theory calculations using the generalized gradient approximation (GGA) and similar results are o…
Direct Energy Minimization Based on Exponential Transformation in Density Functional Calculations of Finite and Extended Systems
Aleksei V. Ivanov, Elvar Ö. Jónsson, Tejs Vegge +1
The energy minimization involved in density functional calculations of electronic systems can be carried out using an exponential transformation that preserves the orthonormality o…
Variational density functional calculations of excited states via direct optimization
Gianluca Levi, Aleksei V. Ivanov, Hannes Jónsson
The development of variational density functional theory approaches to excited electronic states is impeded by limitations of the commonly used self-consistent field (SCF) procedur…
Efficient Optimization Method for Finding Minimum Energy Paths of Magnetic Transitions
Aleksei V. Ivanov, Damjan Dagbartsson, Julien Tranchida +2
Efficient algorithms for the calculation of minimum energy paths of magnetic transitions are implemented within the geodesic nudged elastic band (GNEB) approach. While an objective…
Multiple minimum energy paths and scenarios of unwinding transitions in chiral nematic liquid crystals
Semen S. Tenishchev, Alexei D. Kiselev, Aleksei V. Ivanov +1
We apply the minimum energy paths (MEPs) approach to study the helix unwinding transition in chiral nematic liquid crystals. A mechanism of the transition is determined by a MEP pa…
Fast and Robust Algorithm for the Energy Minimization of Spin Systems Applied in an Analysis of High Temperature Spin Configurations in Terms of Skyrmion Density
Aleksei V. Ivanov, Valery M. Uzdin, Hannes Jónsson
An algorithm for the minimization of the energy of magnetic systems is presented and applied to the analysis of thermal configurations of a ferromagnet to identify inherent structu…
Energy surface and minimum energy paths for Fréedericksz transitions in bistable cholesteric liquid crystals
A. V. Ivanov, P. F. Bessarab, E. V. Aksenova +2
The multidimensional energy surface of a cholesteric liquid crystal in a planar cell is investigated as a function of spherical coordinates determining the director orientation. Mi…