Linear-Scaling Coupled Cluster with Perturbative Triple Excitations: The Divide-Expand-Consolidate CCSD(T) Model.

J Chem Theory Comput

qLEAP Center for Theoretical Chemistry, Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark.

Published: July 2015

We propose a reformulation of the traditional (T) triples correction to the coupled cluster singles and doubles (CCSD) energy in terms of local Hartree-Fock (HF) orbitals such that its structural form aligns with our recently developed linear-scaling divide-expand-consolidate (DEC) coupled cluster family of local correlation methods. In a DEC-CCSD(T) calculation, a basis of local occupied and virtual HF orbitals is used to partition the correlated calculation on the full system into a number of independent atomic fragment and pair fragment calculations, each performed within a truncated set of the complete orbital space. In return, this leads to a massively parallel algorithm for the evaluation of the DEC-CCSD(T) correlation energy, which formally scales linearly with the size of the full system and has a tunable precision with respect to a conventional CCSD(T) calculation via a single energy-based input threshold. The theoretical developments are supported by proof of concept DEC-CCSD(T) calculations on a series of medium-sized molecular systems.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jctc.5b00086DOI Listing

Publication Analysis

Top Keywords

coupled cluster
12
full system
8
linear-scaling coupled
4
cluster perturbative
4
perturbative triple
4
triple excitations
4
excitations divide-expand-consolidate
4
divide-expand-consolidate ccsdt
4
ccsdt model
4
model propose
4

Similar Publications

The cranial mesenchyme, originating from both neural crest and mesoderm, imparts remarkable regional specificity and complexity to postnatal calvarial tissue. While the distinct embryonic origins of the superior and dura periosteum of the cranial parietal bone have been described, the extent of their respective contributions to bone and vessel formation during adult bone defect repair remains superficially explored. Utilizing transgenic mouse models in conjunction with high-resolution multiphoton laser scanning microscopy (MPLSM), we have separately evaluated bone and vessel formation in the superior and dura periosteum before and after injury, as well as following intermittent treatment of recombinant peptide of human parathyroid hormone (rhPTH), Teriparatide.

View Article and Find Full Text PDF

Objective: The effects of sex hormones remain largely unexplored in pheochromocytomas and paragangliomas (PPGLs) and gastroenteropancreatic neuroendocrine tumors (GEP-NETs).

Methods: We evaluated the effects of estradiol, progesterone, Dehydroepiandrosterone sulfate (DHEAS), and testosterone on human patient-derived PPGL/GEP-NET primary culture cell viability (n = 38/n = 12), performed next-generation sequencing and immunohistochemical hormone receptor analysis in patient-derived PPGL tumor tissues (n = 36).

Results: In PPGLs, estradiol and progesterone (1 µm) demonstrated overall significant antitumor effects with the strongest efficacy in PPGLs with NF1 (cluster 2) pathogenic variants.

View Article and Find Full Text PDF

Resonant Auger Decay in Benzene.

J Phys Chem A

January 2025

Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States.

We present ab initio calculations of the resonant Auger spectrum of benzene. In the resonant process, Auger decay ensues following the excitation of a core-level electron to a virtual orbital. Hence, resonant Auger decay gives rise to higher-energy Auger electrons compared to nonresonant decay.

View Article and Find Full Text PDF

Viedma deracemization mechanisms in self-assembly processes.

Phys Chem Chem Phys

January 2025

Laboratoire Softmat, UMR au CNRS no 5623, Université Paul Sabatier, F-31062 Toulouse, France.

Simulations on an ODE-based model shows that there are many common points between Viedma deracemization and chiral self-assemblies of achiral building blocks towards chiral nanoparticles. Both systems occur in a closed system with energy exchange but no matter exchange with the surroundings and show parallel reversible growth mechanisms which coexist with an irreversible cluster breaking (grinding). The various mechanisms of growth give rise to the formation of polymerization/depolymerization cycles while the consecutive transformation of achiral monomer into chiral cluster results into an indirect enantioselective autocatalysis.

View Article and Find Full Text PDF

Magnesium-containing molecules, including MgCH, MgCH, and MgCH, have been detected in the interstellar medium, largely facilitated by their high dipole moments. However, despite great efforts, MgCH species remain elusive. Given the challenges in obtaining experimental data for these molecules, theoretical studies play a crucial role in guiding their detection.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!