TURBOMOLE: Modular program suite for ab initio quantum-chemical and condensed-matter simulations

The Journal of Chemical Physics, Journal Year: 2020, Volume and Issue: 152(18)

Published: May 13, 2020

TURBOMOLE is a collaborative, multi-national software development project aiming to provide highly efficient and stable computational tools for quantum chemical simulations of molecules, clusters, periodic systems, solutions. The suite optimized widely available, inexpensive, resource-efficient hardware such as multi-core workstations small computer clusters. specializes in electronic structure methods with outstanding accuracy-cost ratio, density functional theory including local hybrids the random phase approximation (RPA), GW-Bethe-Salpeter methods, second-order Møller-Plesset theory, explicitly correlated coupled-cluster methods. based on Gaussian basis sets has been pivotal many fast low-scaling algorithms past three decades, integral-direct multipole resolution-of-the-identity approximation, imaginary frequency integration, Laplace transform, pair natural orbital This review focuses recent additions TURBOMOLE's functionality, excited-state RPA Green's function relativistic approaches, high-order molecular properties, solvation effects, systems. A variety illustrative applications along accuracy timing data are discussed. Moreover, available interfaces users well other summarized. current licensing, distribution, support model discussed, an overview workflow provided. Challenges communication outreach, infrastructure, funding highlighted.

Language: Английский

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Theory and Calculation of the Phosphorescence Phenomenon

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(9), P. 6500 - 6537

Published: April 7, 2017

Phosphorescence is a phenomenon of delayed luminescence that corresponds to the radiative decay molecular triplet state. As general property molecules, phosphorescence represents cornerstone problem chemical physics due spin prohibition underlying triplet-singlet emission and because its analysis embraces deep knowledge electronic structure. simplest physical process which provides an example spin-forbidden transformation with characteristic selectivity magnetic field dependence, being model also for more complicated reactions catalysis applications. The bridging in commonly analyzed by perturbation theory, considers intensity borrowing from spin-allowed transitions. In this review, we highlight basic theoretical principles computational aspects estimation various parameters, like intensity, rate constant, lifetime, polarization, zero-field splitting, sublevel population. Qualitative are discussed terms concepts structure–activity relationships, donor–acceptor interactions, vibronic activity, role spin–orbit coupling under charge-transfer perturbations. We illustrate theory highlighting studies classical examples nitrogen oxygen, benzene, naphthalene their azaderivatives, porphyrins, as well reviewing current research on systems electrophosphorescent transition metal complexes, nucleobases, amino acids. furthermore discuss modern cover topics applied relevance, design novel photofunctional materials organic light-emitting diodes (OLEDs), photovoltaic cells, sensors, bioimaging.

Language: Английский

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Multireference Approaches for Excited States of Molecules

Chemical Reviews, Journal Year: 2018, Volume and Issue: 118(15), P. 7293 - 7361

Published: July 24, 2018

Understanding the properties of electronically excited states is a challenging task that becomes increasingly important for numerous applications in chemistry, molecular physics, biology, and materials science. A substantial impact exerted by fascinating progress time-resolved spectroscopy, which leads to strongly growing demand theoretical methods describe characteristic features accurately. Whereas electronic ground state problems stable molecules quantum chemical methodology now so well developed informed nonexperts can use it efficiently, situation entirely different concerning investigation states. This review devoted specific class approaches, usually denoted as multireference (MR) methods, generality needed solving many spectroscopic or photodynamical problems. However, understanding proper application these MR often found be difficult due their complexity computational cost. The purpose this provide an overview most facts about approaches available present means collection examples useful information, guide reader performing own applications.

Language: Английский

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Electrons dynamics control by shaping femtosecond laser pulses in micro/nanofabrication: modeling, method, measurement and application

Light Science & Applications, Journal Year: 2017, Volume and Issue: 7(2), P. 17134 - 17134

Published: Aug. 30, 2017

Abstract During femtosecond laser fabrication, photons are mainly absorbed by electrons, and the subsequent energy transfer from electrons to ions is of picosecond order. Hence, lattice motion negligible within pulse duration, whereas photon-electron interactions dominate entire fabrication process. Therefore, must be improved controlling localized transient electron dynamics, which poses a challenge for measuring at level during processes. Pump-probe spectroscopy presents viable solution, can used observe dynamics chemical reaction. In fact, durations shorter than many physical/chemical characteristic times, permits manipulating, adjusting, or interfering with dynamics. we proposed control temporally spatially shaping pulses, further modify materials properties, then adjust material phase change, eventually implement novel method. This review covers our progresses over past decade regarding (EDC) pulses in micro/nanomanufacturing: (1) Theoretical models were developed prove EDC feasibility reveal its mechanisms; (2) on basis theoretical predictions, experiments conducted validate EDC-based Seven examples reported, proves that method significantly improve precision, quality, throughput repeatability effectively micro/nanoscale structures; (3) multiscale measurement system was study fundamentals scale nanosecond millisecond scale; (4) As an example practical applications, employed fabricate some key structures one 16 Chinese National S&T Major Projects, measured using system.

Language: Английский

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Computational Modeling and Simulation of CO₂ Capture by Aqueous Amines

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(14), P. 9524 - 9593

Published: May 18, 2017

We review the literature on use of computational methods to study reactions between carbon dioxide and aqueous organic amines used capture CO2 prior storage, reuse, or sequestration. The focus is largely high level quantum chemical these reactions, although also summarizes research employing hybrid mechanics/molecular mechanics molecular dynamics. critically effects basis set size, method, solvent models, other factors accuracy calculations provide guidance most appropriate methods, expected performance, method limitations, future needs trends. discusses experimental studies amine-CO2 equilibria, kinetics, measurement prediction amine pKa values, degradation amines. Computational simulations reaction mechanisms are comprehensively described, relative merits zwitterion, termolecular, carbamic acid, bicarbonate discussed in context studies. will become an increasingly valuable complementary adjunct experiments for understanding design more efficient agents with acceptable cost toxicities.

Language: Английский

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Photoprotection: extending lessons learned from studying natural sunscreens to the design of artificial sunscreen constituents

Chemical Society Reviews, Journal Year: 2017, Volume and Issue: 46(12), P. 3770 - 3791

Published: Jan. 1, 2017

Ultrafast pump–probe spectroscopies and computational chemistry unravel the excited state photophysics responsible for photostability of molecules in natural commercial sunscreens.

Language: Английский

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The Bethe–Salpeter Equation Formalism: From Physics to Chemistry

The Journal of Physical Chemistry Letters, Journal Year: 2020, Volume and Issue: 11(17), P. 7371 - 7382

Published: Aug. 7, 2020

The Bethe–Salpeter equation (BSE) formalism is steadily asserting itself as a new efficient and accurate tool in the ensemble of computational methods available to chemists order predict optical excitations molecular systems. In particular, combination so-called GW approximation, giving access reliable ionization energies electron affinities, BSE formalism, able model UV/vis spectra, has shown provide singlet excitation with typical error 0.1–0.3 eV. With similar cost time-dependent density-functional theory (TD-DFT), an accuracy on par most global range-separated hybrid functionals without unsettling choice exchange–correlation functional, resolving further known issues (e.g., charge-transfer excitations). this Perspective, we historical overview BSE, particular focus its condensed-matter roots. We also propose critical review strengths weaknesses different chemical situations.

Language: Английский

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Electronic Structure Methods for the Description of Nonadiabatic Effects and Conical Intersections

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(15), P. 9407 - 9449

Published: June 22, 2021

Nonadiabatic effects are ubiquitous in photophysics and photochemistry, therefore, many theoretical developments have been made to properly describe them. Conical intersections central nonadiabatic processes, as they promote efficient ultrafast transitions between electronic states. A proper description requires structure specifically methods that conical states coupling terms. This review focuses on the aspects of processes. We discuss requirements couplings, how most common excited state perform describing these effects, what recent expanding methodology implementing couplings.

Language: Английский

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Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption

Nature Communications, Journal Year: 2017, Volume and Issue: 8(1)

Published: June 16, 2017

Organic chromophores with heteroatoms possess an important excited state relaxation channel from optically allowed {\pi}{\pi}* to a dark n{\pi}*state. We exploit the element and site specificity of soft x-ray absorption spectroscopy selectively follow electronic change during {\pi}{\pi}*/n{\pi}* internal conversion. As hole forms in n orbital conversion, near edge fine structure (NEXAFS) spectrum at heteroatom K-edge exhibits additional resonance. demonstrate concept nucleobase thymine, prototypical heteroatomic chromophore. With help time resolved NEXAFS oxygen K-edge, we unambiguously show that conversion takes place within (60 \pm 30) fs. High-level coupled cluster calculations on isolated molecules used experiment confirm superb sensitivity this new method for investigations.

Language: Английский

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Exploring Potential Energy Surfaces for Aggregation‐Induced Emission—From Solution to Crystal

Chemistry - An Asian Journal, Journal Year: 2018, Volume and Issue: 14(6), P. 700 - 714

Published: Dec. 10, 2018

Aggregation-induced emission (AIE) is a phenomenon where non-luminescent compounds in solution become strongly luminescent aggregate and solid phase. It provides fertile ground for applications that has rapidly developed the last 15 years. In this review, we focus on contributions of theory computations to understanding molecular mechanism behind it. Starting from initial models, such as restriction intramolecular rotations (RIR), calculation non-radiative rates with Fermi's golden rule (FGR), center studies global excited-state potential energy surfaces have provided basis restricted access conical intersection (RACI) model. model, which been shown apply diverse group AIEgens, lack fluorescence comes radiationless decay at CI hindered state. We also highlight how intermolecular interactions modulate photophysics phase, terms quantum yield color.

Language: Английский

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