Evaluation of Spin-Orbit Couplings with Linear-Response Time-Dependent Density Functional Methods

Gao, Xing; Bai, Shuming; Fazzi, Daniele; Niehaus, Thomas A.; Barbatti, Mario; Thiel, Walter

doi:10.1021/acs.jctc.6b00915

Cited by 312 publications

(332 citation statements)

References 108 publications

Supporting

Mentioning

298

Contrasting

Order By: Relevance

“…[29][30][31][32][33] Nevertheless, the designing of pure light-atoms organic phosphorescent chromophores has still been a significant challenge because of their tiny SOC, ranging from around 1 cm -1 in El-Sayed 34 forbidden transitions to typically 50 to 100 cm -1 in El-Sayed allowed transitions. [35][36] Such SOC values are truly too small compared to those above 500 cm -1 observed in organometallic systems, 37 especially considering that the ISC rate depends on their squared values.…”

Section: Toc Graphicmentioning

confidence: 99%

Promoting Intersystem Crossing of a Fluorescent Molecule via Single Functional Group Modification

Liu

Gao

Barbatti

et al. 2019

J. Phys. Chem. Lett.

Self Cite

View full text Add to dashboard Cite

Pure light-atoms organic phosphorescent molecules have been under scientific scrutiny because they are inexpensive, flexible, and environment friendly.The development of such materials, however, faces a bottleneck problem of intrinsically small spin-orbit couplings (SOC), which can be addressed by seeking a proper balance between intersystem crossing (ISC) and fluorescence rates. Using Nsubstituted naphthalimides (NNI) as the prototype molecule, we applied chemical modifications with several electrophilic and nucleophilic functional groups, to approach the goal. The selected electron donating groups actively restrain the fluorescence, enabling an efficient ISC to the triplet manifold. Electron withdrawing groups do not change the luminescent properties of the parent species. The changes in ISC and fluorescence rates are related to the nature of the lowest singlet state, which changes from localized excitation into charge-transfer excitation. This finding opens an alternative strategy for designing pure light-atoms organic phosphorescent molecules for emerging luminescent materials applications.It has been reported that small ST E  led to efficient ISC and thereby strong phosphorescence in dibenzothiophene-S,S-dioxide and 2-biphenyl-4,6-bis(12phenylindolo[2,3-a]carbazole-11-yl)-1,3,5-triazine complexes. [26][27] In suitable conditions, the metal-ligand compounds may emit phosphorescence thanks to the ligand-localized nature ( 3 IL * or 3 π-π * ) of the lowest triplet state and the relaxation of 3 LMCT/ 3 MLCT to 3 πLC * . 28 However, the risk of toxicity and instability of fluoresce as long as conventional conditions are met: nonradiative rates are small, and the chromophore is in an oxygen-depleted atmosphere. Restrained-fluorescence ISC turns out to be so efficient that it can deplete the singlet population even in systems with spin-orbit couplings as small as those in El-Sayed forbidden transitions.This study cast new insight into the design of pure light-atoms organic phosphorescent molecules via chemical modifications of functional groups. By exploring more organic molecules using the same strategy and employing more comprehensive theoretical framework that can compute phosphorescent radiative decay rate, [44][45] we are on the way of rational design of new organic phosphorescent molecules.The computational details, transition energies, transition related molecular orbitals and corresponding electron-hole distribution of the lowest singlet excited state, the energy level diagrams of low-lying excited states, the Cartesian coordinates of all optimized molecules.

show abstract

Section: Toc Graphicmentioning

confidence: 99%

Promoting Intersystem Crossing of a Fluorescent Molecule via Single Functional Group Modification

Liu

Gao

Barbatti

et al. 2019

J. Phys. Chem. Lett.

Self Cite

View full text Add to dashboard Cite

show abstract

“…390,406 A recently developed external code, PYSOC, enables calculations of spin-orbit couplings with LR-TDDFT. 373 COBRAMM from Garavelli and coworkers is tailored to perform MCSCF/MM simulations of organic and biomolecular systems within the FSSH approximation. [428][429] TSH within QM/MM 73 partitions is also included in NEWTON-X, CPMD, 371 and in a development version of CHEMSHELL.…”

Section: Software Resources For Na-mqc Dynamicsmentioning

confidence: 99%

Recent Advances and Perspectives on Nonadiabatic Mixed Quantum–Classical Dynamics

2018

Self Cite

View full text Add to dashboard Cite

Nonadiabatic mixed quantum-classical (NA-MQC) dynamics methods form a class of computational theoretical approaches in quantum chemistry tailored to investigate the time evolution of nonadiabatic phenomena in molecules and supramolecular assemblies. NA-MQC is characterized by a partition of the molecular system into two subsystems: one to be treated quantum mechanically (usually but not restricted to electrons) and another to be dealt with classically (nuclei). The two subsystems are connected through nonadiabatic couplings terms to enforce self-consistency. A local approximation underlies the classical subsystem, implying that direct dynamics can be simulated, without needing precomputed potential energy surfaces. The NA-MQC split allows reducing computational costs, enabling the treatment of realistic molecular systems in diverse fields. Starting from the three most well-established methods-mean-field Ehrenfest, trajectory surface hopping, and multiple spawning-this review focuses on the NA-MQC dynamics methods and programs developed in the last 10 years. It stresses the relations between approaches and their domains of application. The electronic structure methods most commonly used together with NA-MQC dynamics are reviewed as well. The accuracy and precision of NA-MQC simulations are critically discussed, and general guidelines to choose an adequate method for each application are delivered.

show abstract

“…The optimizations and excitation energy of three compounds structures were performed under M06‐2X‐D3/6‐31G(d) level. Spin–orbit coupling matrix elements between singlet ant triplet states were also calculated by PySOC code …”

Section: Methodsmentioning

confidence: 99%

Controlling Organic Room Temperature Phosphorescence through External Heavy‐Atom Effect for White Light Emission and Luminescence Printing

She

Qin

et al. 2019

Advanced Optical Materials

View full text Add to dashboard Cite

Pure organic materials with tunable room temperature phosphorescence (RTP) have attracted considerable interest because they are promising candidates for a wide range of optoelectronic applications. Herein, a series of organic compounds of (4‐(9H‐carbazol‐9‐yl)butyl) triphenylphosphonium (CBTP) with different halide anions (CBTP‐Cl, CBTP‐Br, and CBTP‐I) are synthesized. They show emission color changes from blue to orange‐red in the solid state. Single‐crystal X‐ray diffraction analysis and theoretical calculations demonstrate that the RTP is primarily caused by the external heavy‐atom effect (EHE), which enhances the spin–orbit coupling between the singlet and triplet excited states to facilitate the intersystem crossing rate. Distinct white light emission can be achieved using the controllable RTP by doping a certain ratio of potassium iodide (KI) into a polymer matrix containing CBTP‐Cl. Moreover, luminescent information can be recorded on a paper substrate made from a polymer film containing CBTP‐Cl with KI aqueous solution as the ink. The results suggest that rational control of the EHE of these pure organic materials is promising for different optoelectronic applications, including solid‐state lighting, data recording, and security protection.

show abstract

Evaluation of Spin-Orbit Couplings with Linear-Response Time-Dependent Density Functional Methods

Cited by 312 publications

References 108 publications

Promoting Intersystem Crossing of a Fluorescent Molecule via Single Functional Group Modification

Promoting Intersystem Crossing of a Fluorescent Molecule via Single Functional Group Modification

Recent Advances and Perspectives on Nonadiabatic Mixed Quantum–Classical Dynamics

Controlling Organic Room Temperature Phosphorescence through External Heavy‐Atom Effect for White Light Emission and Luminescence Printing

Contact Info

Product

Resources

About