Sub-bandgap charge harvesting and energy up-conversion in metal halide perovskites: ab initio quantum dynamics

npj Computational Materials, Journal Year: 2025, Volume and Issue: 11(1)

Published: Jan. 11, 2025

Metal halide perovskites (MHPs) exhibit unusual properties and complex dynamics. By combining ab initio time-dependent density functional theory, nonadiabatic molecular dynamics machine learning, we advance quantum simulation to nanosecond timescale demonstrate that large fluctuations of MHP defect energy levels extend light absorption longer wavelengths enable trapped charges escape into bands. This allows low photons contribute photocurrent through up-conversion. Deep can become shallow transiently vice versa, altering the traditional classification deep. While fluctuate more in MHPs than semiconductors, some levels, e.g., Pb interstitials, remain far from band edges, acting as charge recombination centers. Still, many defects deemed detrimental based on static structures, are fact benign The extended harvesting up-conversion provide strategies for design novel solar, optoelectronic, information devices.

Language: Английский

---

Ab initio nonadiabatic molecular dynamics of charge carriers in metal halide perovskites

Nanoscale, Journal Year: 2021, Volume and Issue: 13(23), P. 10239 - 10265

Published: Jan. 1, 2021

Atomistic details govern quantum dynamics of charge carriers in metal halide perovskites, which exhibit properties solid state and molecular semiconductors, as revealed by time-domain density functional theory nonadiabatic dynamics.

Language: Английский

---

NEXMD Software Package for Nonadiabatic Excited State Molecular Dynamics Simulations

Journal of Chemical Theory and Computation, Journal Year: 2020, Volume and Issue: 16(9), P. 5771 - 5783

Published: July 8, 2020

We present a versatile new code released for open community use, the nonadiabatic excited state molecular dynamics (NEXMD) package. This software aims to simulate using several semiempirical Hamiltonian models. To model such of system, NEXMD uses fewest-switches surface hopping algorithm, where probability transition from one another depends on strength derivative coupling. In addition, there are number algorithmic improvements as empirical decoherence corrections and tracking trivial crossings electronic states. While primary intent behind was dynamics, can also perform geometry optimizations, adiabatic single-point calculations all in vacuum or simulated solvent. this report, first, we lay out basic theoretical framework underlying code. Then code's structure workflow. demonstrate functionality detail, analyze photoexcited polyphenylene ethynylene dendrimer (PPE, C30H18) continuum Furthermore, PPE molecule example serves highlight utility getexcited.py helper script form streamlined script, provided with package, both set up results, including, but not limited to, collecting populations, generating an average optical spectrum, restarting unfinished calculations.

Language: Английский

---

Nonadiabatic Molecular Quantum Dynamics with Quantum Computers

Physical Review Letters, Journal Year: 2020, Volume and Issue: 125(26)

Published: Dec. 31, 2020

The theoretical investigation of non-adiabatic processes is hampered by the complexity coupled electron-nuclear dynamics beyond Born-Oppenheimer approximation. Classically, simulation such reactions limited unfavourable scaling computational resources as a function system size. While quantum computing exhibits proven advantage for real-time dynamics, study algorithms description phenomena still unexplored. In this work, we propose algorithm fast chemical together with an initialization scheme hardware calculations. particular, introduce first-quantization method time evolution wavepacket on two harmonic potential energy surfaces (Marcus model). our approach, scale polynomially in dimensions, opening up new avenues photophysical that are classically intractable.

Language: Английский

---

Machine learning and excited-state molecular dynamics

Machine Learning Science and Technology, Journal Year: 2020, Volume and Issue: 1(4), P. 043001 - 043001

Published: June 12, 2020

Abstract Machine learning is employed at an increasing rate in the research field of quantum chemistry. While majority approaches target investigation chemical systems their electronic ground state, inclusion light into processes leads to electronically excited states and gives rise several new challenges. Here, we survey recent advances for excited-state dynamics based on machine learning. In doing so, highlight successes, pitfalls, challenges future avenues light-induced molecular processes.

Language: Английский

---

Newton-X Platform: New Software Developments for Surface Hopping and Nuclear Ensembles

Journal of Chemical Theory and Computation, Journal Year: 2022, Volume and Issue: 18(11), P. 6851 - 6865

Published: Oct. 4, 2022

Newton-X is an open-source computational platform to perform nonadiabatic molecular dynamics based on surface hopping and spectrum simulations using the nuclear ensemble approach. Both are among most common methodologies in chemistry for photophysical photochemical investigations. This paper describes main features of these methods how they implemented Newton-X. It emphasizes newest developments, including zero-point-energy leakage correction, complex-valued potential energy surfaces, induced by incoherent light, machine-learning potentials, exciton multiple chromophores, supervised unsupervised machine learning techniques. interfaced with several third-party quantum-chemistry programs, spanning a broad electronic structure methods.

Language: Английский

---

A New Frontier in Exciton Transport: Transient Delocalization

The Journal of Physical Chemistry Letters, Journal Year: 2022, Volume and Issue: 13(29), P. 6820 - 6830

Published: July 20, 2022

Efficient exciton transport is crucial to the application of organic semiconductors (OSCs) in light-harvesting devices. While physics highly disordered media well-explored, description structurally and energetically ordered OSCs less established, despite such materials being favorable for In this Perspective we describe highlight recent research pointing toward a efficient mechanism which occurs OSCs, transient delocalization. Here, exciton–phonon couplings play critical role allowing localized states temporarily access higher-energy delocalized whereupon they move large distances. The shows great promise facilitating long-range may allow improved device efficiencies new architectures. However, many fundamental questions on delocalization remain be answered. These suggested next steps are summarized.

Language: Английский

---

Quantum self-consistent equation-of-motion method for computing molecular excitation energies, ionization potentials, and electron affinities on a quantum computer

Chemical Science, Journal Year: 2023, Volume and Issue: 14(9), P. 2405 - 2418

Published: Jan. 1, 2023

Near-term quantum computers are expected to facilitate material and chemical research through accurate molecular simulations. Several developments have already shown that ground-state energies for small molecules can be evaluated on present-day devices. Although electronically excited states play a vital role in processes applications, the search reliable practical approach routine excited-state calculations near-term devices is ongoing. Inspired by methods developed unitary coupled-cluster theory chemistry, we present an equation-of-motion-based method compute excitation following variational eigensolver algorithm computer. We perform numerical simulations H2, H4, H2O, LiH test our self-consistent equation-of-motion (q-sc-EOM) compare it other current state-of-the-art methods. q-sc-EOM makes use of operators satisfy vacuum annihilation condition, critical property calculations. It provides real size-intensive energy differences corresponding vertical energies, ionization potentials electron affinities. also find more suitable implementation NISQ as resilient noise compared with currently available

Language: Английский

---

From a one-mode to a multi-mode understanding of conical intersection mediated ultrafast organic photochemical reactions

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(8), P. 2643 - 2687

Published: Jan. 1, 2023

Over the last few decades, conical intersections (CoIns) have grown from theoretical curiosities into common mechanistic features of photochemical reactions, whose function is to funnel electronically excited molecules back their ground state in regions where potential energy surfaces (PESs) two electronic states become degenerate. Analogous transition thermal chemistry, CoIns appear as transient structures providing a kinetic bottleneck along reaction coordinate. However, such not associated with probability crossing an barrier but rather decay full "line" connected by non-reactive modes, intersection space (IS). This article will review our understanding factors controlling CoIn mediated ultrafast taking physical organic chemist approach discussing number case studies for small and photoactive proteins. Such discussion be carried out first introducing "standard" one-mode model based on Landau-Zener (LZ) theory describe reactive event intercepting, locally, single direction, then modern perspective effects phase matching multiple modes same local event, thus redefining expanding description The direct proportionality between slope (or velocity) one mode at widely applied fundamental principle that follows LZ model, yet it fails provide complete reactions coordinate changes IS. We show these situations, particular focussing rhodopsin double bond photoisomerization, mandatory consider additional molecular relationship approaching IS, hence key photochemistry those modes. anticipate this qualitative should considered rational design any process, impacting various fields research ranging photobiology light-driven devices.

Language: Английский

---

Observation of Wave-Packet Branching through an Engineered Conical Intersection

Physical Review X, Journal Year: 2023, Volume and Issue: 13(1)

Published: Jan. 26, 2023

Analog quantum simulators, which efficiently represent model systems, have the potential to provide new insight toward naturally occurring phenomena beyond capabilities of classical computers. Incorporating dissipation as a resource unlocks wider range out-of-equilibrium processes such chemical reactions. Here, we operate hybrid qubit-oscillator circuit electrodynamics simulator and nonadiabatic molecular dynamics through conical intersection. We identify dephasing electronic qubit mechanism that drives wave-packet branching when corresponding oscillator undergoes large amplitude motion. Furthermore, directly observe enhanced passes Thus, forces influence reaction can be viewed from perspective measurement backaction in mechanics—there is an effective measurement-induced rate depends on position wave packet relative Our results set groundwork for more complex simulations using offering deeper into role determining macroscopic quantities interest yield reaction.5 MoreReceived 16 May 2022Revised 1 November 2022Accepted 19 December 2022DOI:https://doi.org/10.1103/PhysRevX.13.011008Published by American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution this work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasQuantum information processing with continuous variablesQuantum simulationQuantum Information

Language: Английский

---