A new approach to molecular dynamics with non-adiabatic and spin-orbit effects with applications to QM/MM simulations of thiophene and selenophene

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F17%3A00484085" target="_blank" >RIV/61388955:_____/17:00484085 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11310/17:10372892

Výsledek na webu

<a href="http://dx.doi.org/10.1063/1.4978289" target="_blank" >http://dx.doi.org/10.1063/1.4978289</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1063/1.4978289" target="_blank" >10.1063/1.4978289</a>

Jazyk výsledku

angličtina

Název v původním jazyce

A new approach to molecular dynamics with non-adiabatic and spin-orbit effects with applications to QM/MM simulations of thiophene and selenophene

Popis výsledku v původním jazyce

We present surface hopping dynamics on potential energy surfaces resulting from the spin-orbit splitting, i.e., surfaces corresponding to the eigenstates of the total electronic Hamiltonian including the spin-orbit coupling. In this approach, difficulties arise because of random phases of degenerate eigenvectors and possibility of crossings of the resulting mixed states. Our implementation solves these problems and allows propagation of the coefficients both in the representation of the spin free Hamiltonian and directly in the „diagonal representation“ of the mixed states. We also provide a detailed discussion of the state crossing and point out several peculiarities that were not mentioned in the previous literature. We also incorporate the effect of the environment via the quantum mechanics/molecular mechanics approach. As a test case, we apply our methodology to deactivation of thiophene and selenophene in the gas phase, ethanol solution, and bulk liquid phase. First, 100 trajectories without spin-orbit coupling have been calculated for thiophene starting both in S-1 and S-2 states. A subset of 32 initial conditions starting in the S-2 state was then used for gas phase simulations with spin-orbit coupling utilizing the 3-step integrator of SHARC, our implementation of the 3-step propagator in Newton-X and two new „one-step“ approaches. Subsequently, we carried out simulations in ethanol solution and bulk liquid phase for both thiophene and selenophene. For both molecules, the deactivation of the S-2 state proceeds via the ring opening pathway. The total population of triplet states reaches around 15% and 40% after 80 fs for thiophene and selenophene, respectively. However, it only begins growing after the ring opening is initiated. Hence, the triplet states do not directly contribute to the deactivation mechanism...

Název v anglickém jazyce

A new approach to molecular dynamics with non-adiabatic and spin-orbit effects with applications to QM/MM simulations of thiophene and selenophene

Popis výsledku anglicky

We present surface hopping dynamics on potential energy surfaces resulting from the spin-orbit splitting, i.e., surfaces corresponding to the eigenstates of the total electronic Hamiltonian including the spin-orbit coupling. In this approach, difficulties arise because of random phases of degenerate eigenvectors and possibility of crossings of the resulting mixed states. Our implementation solves these problems and allows propagation of the coefficients both in the representation of the spin free Hamiltonian and directly in the „diagonal representation“ of the mixed states. We also provide a detailed discussion of the state crossing and point out several peculiarities that were not mentioned in the previous literature. We also incorporate the effect of the environment via the quantum mechanics/molecular mechanics approach. As a test case, we apply our methodology to deactivation of thiophene and selenophene in the gas phase, ethanol solution, and bulk liquid phase. First, 100 trajectories without spin-orbit coupling have been calculated for thiophene starting both in S-1 and S-2 states. A subset of 32 initial conditions starting in the S-2 state was then used for gas phase simulations with spin-orbit coupling utilizing the 3-step integrator of SHARC, our implementation of the 3-step propagator in Newton-X and two new „one-step“ approaches. Subsequently, we carried out simulations in ethanol solution and bulk liquid phase for both thiophene and selenophene. For both molecules, the deactivation of the S-2 state proceeds via the ring opening pathway. The total population of triplet states reaches around 15% and 40% after 80 fs for thiophene and selenophene, respectively. However, it only begins growing after the ring opening is initiated. Hence, the triplet states do not directly contribute to the deactivation mechanism...

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/GAP208%2F12%2F0559" target="_blank" >GAP208/12/0559: Ab initio molekulová dynamika s neadiabatickými a spinorbitálními efekty aplikovaná na časově závislou fluorescenci</a><br>

Návaznosti

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

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Journal of Chemical Physics

ISSN

0021-9606

e-ISSN

—

Svazek periodika

146

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

—

Kód UT WoS článku

000397313600003

EID výsledku v databázi Scopus

2-s2.0-85015711502