Modeling Liquid Photoemission Spectra: Path-Integral Molecular Dynamics Combined with Tuned Range-Separated Hybrid Functionals

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F16%3A43902484" target="_blank" >RIV/60461373:22340/16:43902484 - isvavai.cz</a>

Výsledek na webu

<a href="http://pubs.acs.org/doi/abs/10.1021/acs.jctc.6b00630?journalCode=jctcce" target="_blank" >http://pubs.acs.org/doi/abs/10.1021/acs.jctc.6b00630?journalCode=jctcce</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jctc.6b00630" target="_blank" >10.1021/acs.jctc.6b00630</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Modeling Liquid Photoemission Spectra: Path-Integral Molecular Dynamics Combined with Tuned Range-Separated Hybrid Functionals

Popis výsledku v původním jazyce

We present a computational protocol for modeling valence photoemission spectra of liquids. We use water as an experimentally well-characterized model system, and we represent its liquid state by larger finite-sized droplets. The photoemission spectrum is evaluated for an ensemble of structures along molecular dynamics simulations. The nuclear quantum effects are accounted for by ab initio based path-integral molecular dynamics simulations that are greatly accelerated with the so-called colored noise thermostat (PI+GLE) method. The ionization energies for the valence electrons are evaluated as orbital energies of optimally tuned range-separated hybrid functionals (OT-RSH). This approach provides Koopmans-type ionization energies including relaxation energy. We show that the present protocol can quantitatively describe the valence photoemission spectrum of liquid water, i.e., the positions, shapes, and widths of the photoemission peaks. With the PI+GLE simulations, even the subtle isotope effects that have been recently observed experimentally can be modeled. The electronic properties of finite-sized droplets are shown to converge rapidly to those of liquids. We discuss the importance of proper tuning of the range-separation parameter in OT-RSH as well as possible sources of error in our simulations. The present approach seems to be a viable route to modeling photoemission spectra of liquids, especially in conjunction with efficient implementation of density functional methods on graphical processing units.

Název v anglickém jazyce

Modeling Liquid Photoemission Spectra: Path-Integral Molecular Dynamics Combined with Tuned Range-Separated Hybrid Functionals

Popis výsledku anglicky

We present a computational protocol for modeling valence photoemission spectra of liquids. We use water as an experimentally well-characterized model system, and we represent its liquid state by larger finite-sized droplets. The photoemission spectrum is evaluated for an ensemble of structures along molecular dynamics simulations. The nuclear quantum effects are accounted for by ab initio based path-integral molecular dynamics simulations that are greatly accelerated with the so-called colored noise thermostat (PI+GLE) method. The ionization energies for the valence electrons are evaluated as orbital energies of optimally tuned range-separated hybrid functionals (OT-RSH). This approach provides Koopmans-type ionization energies including relaxation energy. We show that the present protocol can quantitatively describe the valence photoemission spectrum of liquid water, i.e., the positions, shapes, and widths of the photoemission peaks. With the PI+GLE simulations, even the subtle isotope effects that have been recently observed experimentally can be modeled. The electronic properties of finite-sized droplets are shown to converge rapidly to those of liquids. We discuss the importance of proper tuning of the range-separation parameter in OT-RSH as well as possible sources of error in our simulations. The present approach seems to be a viable route to modeling photoemission spectra of liquids, especially in conjunction with efficient implementation of density functional methods on graphical processing units.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

—

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Chemical Theory and Computation

ISSN

1549-9618

e-ISSN

—

Svazek periodika

12

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

"5009?5017"

Kód UT WoS článku

000385336300026

EID výsledku v databázi Scopus

2-s2.0-84991079606