Systematic improvement of molecular excited state calculations by inclusion of nuclear quantum motion: A mode-resolved picture and the effect of molecular size

Organic active nanophotonics: excited-state coupled photonic behaviours strongly determine the optical performances of organic nanomaterials. The photonic actions and related material properties can be well controlled by tailoring the intra/inter-molecular excited-state processes.

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Direct observation of the excited state structure of a Ag(I)-Cu(I) complex

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314092250 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C774-C774 ◽

Cited By ~ 1

Author(s):

Katarzyna Jarzembska ◽

Radoslaw Kaminski ◽

Bertrand Fournier ◽

Elzbieta Trzop ◽

Jesse Sokolow ◽

...

Keyword(s):

Excited State ◽

Solid State ◽

Structural Changes ◽

Luminescent Properties ◽

Crystal Form ◽

Data Sets ◽

Time Resolved ◽

Model Complex ◽

Metal Metal ◽

Molecular Excited State

Heterodentate coordination complexes have been extensively studied because of their rich electronic and luminescent properties, which are of importance in the design of molecular devices. The short metal-metal contacts found in such complexes determine the nature of the lowest lying emissive states, and must be explored in order to understand their physical properties. Recent advances in time-resolved (TR) synchrotron techniques supported by specific data collection strategies and data processing procedures [1] allow for elucidation of molecular excited state geometries in the solid state. The approach has been so far successfully applied to several high-quality Laue-data sets collected at the 14-ID BioCars beamline at the Advanced Photon Source.[2] In this contribution we present synchrotron TR experiment results obtained for a new solvent-free crystal form of a model complex containing Ag(I) and Cu(I) (Ag2Cu2L4, L = 2-diphenylphosphino-3-methylindole).[3] This system exhibits red solid-state luminescence with a lifetime of about 1 µs. This is one of the shortest-lived excited states we have studied so far with the Laue technique. The relatively short lifetime goes along with significant structural changes observed upon irradiation, such as, the Ag...Ag distance shortening of about 0.2 Å in the excited state. The results clearly show strengthening of the Ag...Ag interactions suggesting a bond formation upon excitation. The photocrystallographic findings are supported by spectroscopic measurements and quantum computations. The results confirm the triplet nature of the emissive state originating mainly from a ligand-to-metal charge transfer. Research funded by the NSF (CHE1213223). BioCARS Sector 14 is supported by NIH, National Center for Research Resources (RR007707). APS is funded by the U.S. DOE, Office of Basic Energy Sciences (W-31-109-ENG-38). KNJ is supported by the Polish Ministry of Science and Higher Education through the "Mobility Plus" program.

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Role of Solvent, pH, and Molecular Size in Excited-State Deactivation of Key Eumelanin Building Blocks: Implications for Melanin Pigment Photostability

Journal of the American Chemical Society ◽

10.1021/ja806345q ◽

2008 ◽

Vol 130 (50) ◽

pp. 17038-17043 ◽

Cited By ~ 59

Author(s):

M. Gauden ◽

A. Pezzella ◽

L. Panzella ◽

M. T. Neves-Petersen ◽

E. Skovsen ◽

...

Keyword(s):

Excited State ◽

Molecular Size ◽

Building Blocks ◽

Melanin Pigment ◽

Role Of Solvent

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Developing a chemical database to store and analyze molecular excited state information

10.1021/scimeetings.0c00177 ◽

2020 ◽

Author(s):

Christian Dwyer

Keyword(s):

Excited State ◽

State Information ◽

Chemical Database ◽

Molecular Excited State

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Analytical Derivatives of the Individual State Energies in Ensemble Density Functional Theory Method: II. Implementation on Graphical Processing Units (GPUs)

10.26434/chemrxiv.7985657.v1 ◽

2019 ◽

Cited By ~ 5

Author(s):

Fang Liu ◽

Michael Filatov ◽

Todd J. Martínez

Keyword(s):

Excited State ◽

Density Functional ◽

Density Functional Theory Method ◽

Molecular Size ◽

Conical Intersections ◽

Computationally Efficient ◽

Graphical Processing Units ◽

Analytical Derivatives ◽

Graphical Processing ◽

The Individual

Conical intersections control excited state reactivity and thus elucidation and prediction of their shapes and locations is crucial for photochemistry. To locate these intersections one needs accurate and efficient electronic structure methods. Unfortunately, the most accurate methods (e.g. XMS-CASPT2) are computationally difficult for large molecules. The state-interaction state-averaged restricted ensemble referenced Kohn-Sham (SI-SA-REKS) method is a computationally efficient alternative. The application of SI-SA-REKS to photochemistry was previously hampered by a lack of analytical nuclear gradients and nonadiabatic coupling matrix elements. We have recently derived analytical energy derivatives for the SI-SA-REKS method and implemented the method effectively on graphical processing units (GPUs). We demonstrate that our implementation gives the correct topography and energetics of conical intersections for several examples. Furthermore, our implementation of SI-SA-REKS is computationally efficient – the observed scaling with molecular size is sub-quadratic, i.e. O(N<sup>1.77</sup>). This demonstrates the promise of SI-SA-REKS for excited state dynamics of large molecular systems.

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