Zobrazeno 1 - 10
of 240
pro vyhledávání: '"Krakauer, Henry"'
Publikováno v:
J. Chem. Phys. 158, 234110 (2023)
Molecular magnets have received significant attention because of their potential applications in quantum information and quantum computing. A delicate balance of electron correlation, spin-orbit coupling (SOC), ligand field splitting, and other effec
Externí odkaz:
http://arxiv.org/abs/2303.09010
Publikováno v:
J. Chem. Phys. 156, 014107 (2022)
We incorporate explicit, non-perturbative treatment of spin-orbit coupling into ab initio auxiliary-field quantum Monte Carlo (AFQMC) calculations. The approach allows a general computational framework for molecular and bulk systems in which material
Externí odkaz:
http://arxiv.org/abs/2110.10201
Publikováno v:
J. Chem. Theory Comput. 2019, 15, 7, 3949-3959
A local embedding and effective downfolding scheme has been developed and implemented in the auxiliary-field quantum Monte Carlo (AFQMC) method. A local cluster in which electrons are fully correlated is defined and the frozen orbital method is used
Externí odkaz:
http://arxiv.org/abs/1812.05471
Publikováno v:
Phys. Rev. B 95, 165103 (2017)
We have implemented recently developed multiple-projector pseudopotentials into the planewave based auxiliary-field quantum Monte Carlo (pw-AFQMC) method. Multiple-projector pseudopotentials can yield smaller planewave cut-offs while maintaining or i
Externí odkaz:
http://arxiv.org/abs/1610.06267
Publikováno v:
J. Chem. Phys. 144, 244306 (2016)
Chemical accuracy is difficult to achieve for systems with transition metal atoms. Third row transition metal atoms are particularly challenging due to strong electron-electron correlation in localized d-orbitals. The Cr2 molecule is an outstanding e
Externí odkaz:
http://arxiv.org/abs/1603.07336
Autor:
Komelj, Matej, Krakauer, Henry
Publikováno v:
Phys. Rev. B 92, 205125 (2015)
We investigate the ${\rm H_3S}$ phase of sulphur hydride under high pressure $\simeq$ 200 GPa by means of {\it ab-initio} calculations within the framework of the density-functional theory (DFT) with the PBE0 hybrid exchange-correlation ($E_{\rm xc}$
Externí odkaz:
http://arxiv.org/abs/1509.01297
Publikováno v:
Phys. Rev. Lett. 114, 226401 (2015)
We present a systematic downfolding many-body approach for extended systems. Many-body calculations operate on a simpler Hamiltonian which retains material-specific properties. The Hamiltonian is systematically improvable and allows one to dial, in p
Externí odkaz:
http://arxiv.org/abs/1412.0322
Publikováno v:
J. Chem. Phys. 142, 064302 (2015)
The chromium dimer (Cr2) presents an outstanding challenge for many-body electronic structure methods. Its complicated nature of binding, with a formal sextuple bond and an unusual potential energy curve, is emblematic of the competing tendencies and
Externí odkaz:
http://arxiv.org/abs/1410.3505
Publikováno v:
Phys. Rev. Lett. 113, 175502 (2014)
We investigate the stability and electronic properties of single Co atoms on graphene with near-exact many-body calculations. A frozen-orbital embedding scheme was combined with auxiliary-field quantum Monte Carlo to increase the reach in system size
Externí odkaz:
http://arxiv.org/abs/1407.0703
Publikováno v:
J. Chem. Theory Comput. 9, 4825 (2013)
We describe the implementation of the frozen-orbital and downfolding approximations in the auxiliary-field quantum Monte Carlo (AFQMC) method. These approaches can provide significant computational savings compared to fully correlating all the electr
Externí odkaz:
http://arxiv.org/abs/1308.1393