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Samuthirapandi K, Durairaj P, Sarkar S. Interfacial Charge Transfer in Photoexcited QD-Molecule Composite of Tetrahedral CdSe Quantum Dot Coupled with Carbazole. ACS APPLIED MATERIALS & INTERFACES 2024; 16:31045-31055. [PMID: 38857441 DOI: 10.1021/acsami.4c02443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Photoexcited charge transfer dynamics in CdSe quantum dots (QDs) coupled with carbazole were explored to model QD-molecule systems for light-harvesting applications. The absorption spectra of QDs with different sizes, i.e., Cd35Se20X30L30 (T1), Cd56Se35X42L42 (T2), and Cd84Se56X56L56 (T3) were simulated with quantum dynamical methods, which qualitatively match the reported experimental spectra. The carbazole is attached with a 3-amino group at the apex position of T1 (namely T1-3A-Cz), establishing proper electronic communication between T1 and carbazole. The spectra of T1-3A-Cz is 0.22 eV red-shifted compared to T1. A time-dependent perturbation was applied in tune with the lowest energy peak (3.63 eV) of T1-3A-Cz to investigate the charge transfer dynamics, which revealed an ultrafast charge separation within the femtosecond time scale. The electronic structure showed a favorable energy alignment between T1 and carbazole in T1-3A-Cz. The LUMO of carbazole was situated below the conduction band of the QD, while the HOMO of carbazole mixed perfectly with the top of the valence band of the QD, developing the interfacial charge transfer states. These states promoted the photoexcited electron transfer directly from the CdSe core to carbazole. A rapid and enhanced charge separation occurred with the laser field strength increasing from 0.001 to 0.005 V/Å. However, T1 connected to the other positions of carbazole did not show charge separation effectively. The photoinduced charge transfer is negligible in the case of T2-carbazole systems due to poor electronic coupling, and it is not observed in T3-carbazole systems. So, the T1-3A-Cz model acts as a perfect donor-acceptor QD-molecule nanocomposite that can harvest photon energy efficiently. Further enhancement of charge transfer can be achieved by coupling more carbazoles to the T1 QD (e.g., T1-3A-Cz2) due to the extension of hole delocalization between T1 and the carbazoles.
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Affiliation(s)
| | - Pandiselvi Durairaj
- Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India
| | - Sunandan Sarkar
- Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India
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2
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Shunaev VV, Pincak R, Glukhova OE. The energetical, electronic and optical properties of the intermetallic fullerene Fe@C60. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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3
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Liu Z, Oviedo MB, Wong BM, Aikens CM. Plasmon-induced excitation energy transfer in silver nanoparticle dimers: A real-time TDDFTB investigation. J Chem Phys 2022; 156:154705. [PMID: 35459307 DOI: 10.1063/5.0082960] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Using real-time quantum dynamics calculations, we perform theoretical investigations of light-induced interactions and electronic excitation transfer in a silver nanoparticle dimer. Real-time time-dependent density functional tight-binding (RT-TDDFTB) calculations provide details of the quantum dynamical processes at an electronic/atomistic level with attosecond resolution. The computational efficiency of RT-TDDFTB allows us to examine electronic dynamics up to picosecond time scales. With time scales varying over six orders of magnitude, we provide insight into interactions between the nanoparticle and laser and between nanoparticles. Our results show that the coupling between nanoparticle monomers is dependent on the separation distance between the nanoparticles in the dimer. As the interparticle distance is varied, the dipole-dipole interactions and electronic excitation transfer mechanisms are markedly different. At large distances (from 50 to 20 Å), the energy transfer from NP1 to NP2 becomes more efficient as the interparticle distance decreases. The total dipole moment of the Ag14 nanoparticle dimer increases linearly at an interparticle distance of 20 Å and reaches its maximum after 1.2 ps. The electronic excitation transfer is also the most efficient at 20 Å. At short distances, back-transfer effects reduce the ability of the dimer and NP1 to accept energy from the incident electric field. We attribute the distance-dependent features of the nanoparticle dimer to the beating between the laser acting on NP1 and the back transfer from NP2 to NP1.
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Affiliation(s)
- Zhen Liu
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Belén Oviedo
- Department of Chemical and Environmental Engineering and Materials Science and Engineering Program, University of California-Riverside, Riverside, California 92521, USA
| | - Bryan M Wong
- Department of Chemical and Environmental Engineering and Materials Science and Engineering Program, University of California-Riverside, Riverside, California 92521, USA
| | - Christine M Aikens
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, USA
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4
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Domínguez-Castro A, Lien-Medrano CR, Maghrebi K, Messaoudi S, Frauenheim T, Fihey A. Photoinduced charge-transfer in chromophore-labeled gold nanoclusters: quantum evidence of the critical role of ligands and vibronic couplings. NANOSCALE 2021; 13:6786-6797. [PMID: 33690747 DOI: 10.1039/d1nr00213a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The electron flow between a metallic aggregate and an organic molecule after excitation with light is a crucial step on which hybrid photovoltaic nanomaterials are based. So far, designing such devices with the help of theoretical approaches has been heavily limited by the computational cost of quantum dynamics models able to track the evolution of the excited states over time. In this article, we present the first application of the time-dependent density functional tight-binding (TD-DFTB) method for an experimental nanometer-sized gold-organic system consisting of a hexyl-protected Au25 cluster labelled with a pyrene fluorophore, in which the fluorescence quenching of the pyrene is attributed to the electron transfer from the metallic cluster to the dye. The full quantum rationalization of the electron transfer is attained through quantum dynamics simulations, highlighting the crucial role of the protecting ligand shell in electron transfer, as well as the coupling with nuclear movement. This work paves the way towards the fast and accurate theoretical design of optoelectronic nanodevices.
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5
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Hashemi Z, Leppert L. Assessment of the Ab Initio Bethe-Salpeter Equation Approach for the Low-Lying Excitation Energies of Bacteriochlorophylls and Chlorophylls. J Phys Chem A 2021; 125:2163-2172. [PMID: 33656894 PMCID: PMC8028335 DOI: 10.1021/acs.jpca.1c01240] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacteriochlorophyll and chlorophyll molecules are crucial building blocks of the photosynthetic apparatus in bacteria, algae, and plants. Embedded in transmembrane protein complexes, they are responsible for the primary processes of photosynthesis: excitation energy and charge transfer. Here, we use ab initio many-body perturbation theory within the GW approximation and Bethe-Salpeter equation (BSE) approach to calculate the electronic structure and optical excitations of bacteriochlorophylls a, b, c, d, and e and chlorophylls a and b. We systematically study the effects of the structure, basis set size, partial self-consistency in GW, and the underlying exchange-correlation approximation and compare our calculations with results from time-dependent density functional theory, multireference RASPT2, and experimental literature results. We find that optical excitations calculated with GW+BSE are in excellent agreement with experimental data, with an average deviation of less than 100 meV for the first three bright excitations of the entire family of (bacterio)chlorophylls. Contrary to state-of-the-art time-dependent density functional theory (TDDFT) with an optimally tuned range-separated hybrid functional, this accuracy is achieved in a parameter-free approach. Moreover, GW+BSE predicts the energy differences between the low-energy excitations correctly and eliminates spurious charge transfer states that TDDFT with (semi)local approximations is known to produce. Our study provides accurate reference results and highlights the potential of the GW+BSE approach for the simulation of larger pigment complexes.
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Affiliation(s)
- Zohreh Hashemi
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany
| | - Linn Leppert
- Institute of Physics, University of Bayreuth, Bayreuth 95440, Germany.,MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands
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6
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Li X, Govind N, Isborn C, DePrince AE, Lopata K. Real-Time Time-Dependent Electronic Structure Theory. Chem Rev 2020; 120:9951-9993. [DOI: 10.1021/acs.chemrev.0c00223] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States
| | - Niranjan Govind
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Christine Isborn
- Department of Chemistry and Chemical Biology, University of California, Merced, California 95343, United States
| | - A. Eugene DePrince
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306-4390, United States
| | - Kenneth Lopata
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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7
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Bonafé FP, Aradi B, Hourahine B, Medrano CR, Hernández FJ, Frauenheim T, Sánchez CG. A Real-Time Time-Dependent Density Functional Tight-Binding Implementation for Semiclassical Excited State Electron–Nuclear Dynamics and Pump–Probe Spectroscopy Simulations. J Chem Theory Comput 2020; 16:4454-4469. [DOI: 10.1021/acs.jctc.9b01217] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Franco P. Bonafé
- Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Teórica y Computacional, Córdoba, Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET - Universidad Nacional de Córdoba), Córdoba, Argentina
| | - Bálint Aradi
- Bremen Center for Computational Materials Science, Universitát Bremen, Bremen, Germany
| | - Ben Hourahine
- SUPA, Department of Physics, John Anderson Building, The University of Strathclyde, 107 Rottenrow, Glasgow G15 6QN, United Kingdom
| | - Carlos R. Medrano
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Teórica y Computacional, Córdoba, Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET - Universidad Nacional de Córdoba), Córdoba, Argentina
| | - Federico J. Hernández
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Teórica y Computacional, Córdoba, Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET - Universidad Nacional de Córdoba), Córdoba, Argentina
- Department of Physics, Universidad de Santiago de Chile, Av. Ecuador 3493, Santiago, Chile
| | - Thomas Frauenheim
- Bremen Center for Computational Materials Science, Universitát Bremen, Bremen, Germany
- Computational Science Research Center (CSRC) Beijing and Computational Science and Applied Research (CSAR) Institute, Shenzhen, China
| | - Cristián G. Sánchez
- Instituto Interdisciplinario de Ciencias Básicas, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Exactas y Naturales, Mendoza, Argentina
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8
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Schelter I, Foerster JM, Gardiner AT, Roszak AW, Cogdell RJ, Ullmann GM, de Queiroz TB, Kümmel S. Assessing density functional theory in real-time and real-space as a tool for studying bacteriochlorophylls and the light-harvesting complex 2. J Chem Phys 2019; 151:134114. [DOI: 10.1063/1.5116779] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Ingo Schelter
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
| | - Johannes M. Foerster
- Theoretical Physics IV and Computational Biochemistry, University of Bayreuth, Bayreuth, Germany
| | | | - Aleksander W. Roszak
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Richard J. Cogdell
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | | | | | - Stephan Kümmel
- Theoretical Physics IV, University of Bayreuth, Bayreuth, Germany
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9
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Quantum Phonon Transport in Nanomaterials: Combining Atomistic with Non-Equilibrium Green's Function Techniques. ENTROPY 2019; 21:e21080735. [PMID: 33267449 PMCID: PMC7515264 DOI: 10.3390/e21080735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 11/16/2022]
Abstract
A crucial goal for increasing thermal energy harvesting will be to progress towards atomistic design strategies for smart nanodevices and nanomaterials. This requires the combination of computationally efficient atomistic methodologies with quantum transport based approaches. Here, we review our recent work on this problem, by presenting selected applications of the PHONON tool to the description of phonon transport in nanostructured materials. The PHONON tool is a module developed as part of the Density-Functional Tight-Binding (DFTB) software platform. We discuss the anisotropic phonon band structure of selected puckered two-dimensional materials, helical and horizontal doping effects in the phonon thermal conductivity of boron nitride-carbon heteronanotubes, phonon filtering in molecular junctions, and a novel computational methodology to investigate time-dependent phonon transport at the atomistic level. These examples illustrate the versatility of our implementation of phonon transport in combination with density functional-based methods to address specific nanoscale functionalities, thus potentially allowing for designing novel thermal devices.
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10
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Hernández FJ, Bonafé FP, Aradi B, Frauenheim T, Sánchez CG. Simulation of Impulsive Vibrational Spectroscopy. J Phys Chem A 2019; 123:2065-2072. [DOI: 10.1021/acs.jpca.9b00307] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Federico J. Hernández
- Universidad Nacional de Córdoba. Facultad de Ciencias Quı́micas, Departamento de Quı́mica Teórica y Computacional, Córdoba Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET-Universidad Nacional de Córdoba), Córdoba 5000, Argentina
| | - Franco P. Bonafé
- Universidad Nacional de Córdoba. Facultad de Ciencias Quı́micas, Departamento de Quı́mica Teórica y Computacional, Córdoba Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET-Universidad Nacional de Córdoba), Córdoba 5000, Argentina
| | - Bálint Aradi
- Bremen Center for Computational Materials Science, Universität Bremen, Bremen 28359, Germany
| | - Thomas Frauenheim
- Bremen Center for Computational Materials Science, Universität Bremen, Bremen 28359, Germany
| | - Cristián G. Sánchez
- Universidad Nacional de Córdoba. Facultad de Ciencias Quı́micas, Departamento de Quı́mica Teórica y Computacional, Córdoba Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba, INFIQC (CONICET-Universidad Nacional de Córdoba), Córdoba 5000, Argentina
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11
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Marquez DM, Sánchez CG. Quantum efficiency of the photo-induced electronic transfer in dye-TiO 2 complexes. Phys Chem Chem Phys 2018; 20:26280-26287. [PMID: 30324945 DOI: 10.1039/c8cp04625e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a method based on a time-dependent self-consistent density functional tight-binding (TD-DFTB) approach, able to predict the quantum efficiency of the photoinjection process in a dye-TiO2 complex from a fully atomistic picture. We studied the process of charge transfer of three systems with different dyes: catechol (CAT), alizarin (ALZ) and FSD101. Each system was excited with lasers of different energies in the range of 300-2500 nm, studying the efficiency of the induced charge transfer process at the incident energies. We show that the perturbation can produce either hole transfer or electron transfer from the dye to the nanoparticle, therefore affecting the efficiency of the charge transfer in the solar cell when illuminated by broadband radiation.
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Affiliation(s)
- Dalma M Marquez
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Teórica y Computacional, Ciudad Universitaria, X5000HUA, Córdoba, Argentina and Instituto de Investigaciones Fisicoquímicas de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina.
| | - Cristián G Sánchez
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Teórica y Computacional, Ciudad Universitaria, X5000HUA, Córdoba, Argentina and Instituto de Investigaciones Fisicoquímicas de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina.
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12
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Bonafé FP, Hernández FJ, Aradi B, Frauenheim T, Sánchez CG. Fully Atomistic Real-Time Simulations of Transient Absorption Spectroscopy. J Phys Chem Lett 2018; 9:4355-4359. [PMID: 30024765 DOI: 10.1021/acs.jpclett.8b01659] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We have implemented an electron-nuclear real-time propagation scheme for the calculation of transient absorption spectra. When this technique is applied to the study of ultrafast dynamics of Soret-excited zinc(II) tetraphenylporphyrin in the subpicosecond time scale, quantum beats in the transient absorption caused by impulsively excited molecular vibrations are observed. The launching mechanism of such vibrations can be regarded as a displacive excitation of the zinc-pyrrole and pyrrole C-C bonds.
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Affiliation(s)
- Franco P Bonafé
- Departamento de Química Teórica y Computacional, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Córdoba , Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba , INFIQC (CONICET - Universidad Nacional de Córdoba) , Córdoba , Argentina
| | - Federico J Hernández
- Departamento de Química Teórica y Computacional, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Córdoba , Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba , INFIQC (CONICET - Universidad Nacional de Córdoba) , Córdoba , Argentina
| | - Bálint Aradi
- Bremen Center for Computational Materials Science , Universität Bremen , Bremen , Germany
| | - Thomas Frauenheim
- Bremen Center for Computational Materials Science , Universität Bremen , Bremen , Germany
| | - Cristián G Sánchez
- Departamento de Química Teórica y Computacional, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Córdoba , Argentina
- Instituto de Investigaciones en Fisicoquímica de Córdoba , INFIQC (CONICET - Universidad Nacional de Córdoba) , Córdoba , Argentina
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13
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Medrano CR, Sánchez CG. Trap-Door-Like Irreversible Photoinduced Charge Transfer in a Donor-Acceptor Complex. J Phys Chem Lett 2018; 9:3517-3524. [PMID: 29888923 DOI: 10.1021/acs.jpclett.8b01043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
For efficient conversion of light into useful energy sources, it is very important to study and describe the first steps of primary charge-transfer process in natural structures and artificial devices. The time scale of these processes in artificial photosynthetic and photovoltaic devices is on the order of femto- to picoseconds and involves vibronic coupling of electrons and nuclei and also nuclear alleviation to enhance charge separation. Here we present an atomistic description of the photoexcited electron dynamics in a noncovalently bonded system formed by an hydrogenated nanodiamond as donor and a perylene diimide as an acceptor. The complex shows extremely fast charge transfer, separation, and stabilization within 90 fs. This stabilization is purely electronic in nature. To the best of our knowledge, these results show for the first time that it is possible to stabilize charge without polaron formation or nuclear relaxation, reaching a steady state enhanced by a pure electronic reorganization.
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Affiliation(s)
- Carlos R Medrano
- Universidad Nacional de Córdoba , Facultad de Ciencias Químicas. Departamento de Química Teórica y Computacional , Ciudad Universitaria , X5000HUA Córdoba , Argentina
- Instituto de Investigaciones Fisicoquímicas de Córdoba , Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET) , Ciudad Universitaria , X5000HUA Córdoba , Argentina
| | - Cristián G Sánchez
- Universidad Nacional de Córdoba , Facultad de Ciencias Químicas. Departamento de Química Teórica y Computacional , Ciudad Universitaria , X5000HUA Córdoba , Argentina
- Instituto de Investigaciones Fisicoquímicas de Córdoba , Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET) , Ciudad Universitaria , X5000HUA Córdoba , Argentina
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14
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Singlet and triplet excited states dynamics of photosynthetic pigment chlorophyll a investigated by sub-nanosecond pump-probe spectroscopy. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2017.09.046] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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Schelter I, Kümmel S. Accurate Evaluation of Real-Time Density Functional Theory Providing Access to Challenging Electron Dynamics. J Chem Theory Comput 2018; 14:1910-1927. [DOI: 10.1021/acs.jctc.7b01013] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ingo Schelter
- Department of Physics, University of Bayreuth, 95440 Bayreuth, Germany
| | - Stephan Kümmel
- Department of Physics, University of Bayreuth, 95440 Bayreuth, Germany
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16
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Berdakin M, Taccone MI, Pino GA, Sánchez CG. DNA-protected silver emitters: charge dependent switching of fluorescence. Phys Chem Chem Phys 2018; 19:5721-5726. [PMID: 28230217 DOI: 10.1039/c6cp08345e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The relationship between the state of charge and spectroscopy of DNA-protected silver emitters is not yet well understood. This remains one of the major issues to unveil in order to fully disentangle the spectroscopic features of these novel systems. It is a well known fact that a fluorescence response arises upon chemical reduction of silver cations attached to DNA, leading to neutral (or partially oxidized) "bright" clusters. It is important to note that the absence of fluorescence in completely ionic complexes is universal in the sense that it does not depend on any experimental variable. This suggests that its origin may be founded on the nature of the interaction between DNA bases and silver cations. Nevertheless, to the best of our knowledge, no explanation exists for this charge dependent switching between dark completely ionic complexes and bright (neutral or partially oxidized) clusters. In this brief report we address this experimental fact on the basis of the electronic structure of the complex as a function of its charge and quantum dynamical simulations of the processes following photoexcitation. These data provide a dynamical picture of the correlation between charge and fluorescence.
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Affiliation(s)
- Matías Berdakin
- INFIQC (UNC-CONICET), Dpto. de Matemática y Física, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina.
| | - Martin I Taccone
- INFIQC (UNC-CONICET), Dpto. de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina
| | - Gustavo A Pino
- INFIQC (UNC-CONICET), Dpto. de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina
| | - Cristián G Sánchez
- INFIQC (UNC-CONICET), Dpto. de Matemática y Física, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Pabellón Argentina, 5000 Córdoba, Argentina.
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17
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Mansilla Wettstein C, Sánchez CG. Characterization of ZnO as substrate for DSSC. Phys Chem Chem Phys 2018; 20:21910-21916. [DOI: 10.1039/c8cp01709c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a complete analysis of the photoinjection process in 3 nm spherical ZnO nanoparticles with different dyes attached to their surface.
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Affiliation(s)
- Candela Mansilla Wettstein
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas
- Departamento de Química Teórica y Computacional
- Ciudad Universitaria X5000HUA
- Córdoba
- Argentina
| | - Cristián G. Sánchez
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas
- Departamento de Química Teórica y Computacional
- Ciudad Universitaria X5000HUA
- Córdoba
- Argentina
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18
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Taccone MI, Berdakin M, Pino GA, Sánchez CG. Optical properties and charge distribution in rod-shape DNA–silver cluster emitters. Phys Chem Chem Phys 2018; 20:22510-22516. [DOI: 10.1039/c8cp03895c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Our results show that the experimental optical properties of DNA–Agn are theoretically reproduced by considering the zigzag rod-shape structure of the metal cluster.
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Affiliation(s)
- Martín I. Taccone
- Departamento de Fisicoquímica
- Fac. de Ciencias Químicas
- Universidad Nacional de Córdoba
- Ciudad Universitaria
- X5000HUA Córdoba
| | - Matías Berdakin
- Departamento de Física
- Facultad de Ciencias Físicas y Matemáticas
- Universidad de Chile
- Santiago
- Chile
| | - Gustavo A. Pino
- Departamento de Fisicoquímica
- Fac. de Ciencias Químicas
- Universidad Nacional de Córdoba
- Ciudad Universitaria
- X5000HUA Córdoba
| | - Cristián G. Sánchez
- INFIQC (CONICET)
- Ciudad Universitaria
- 5000 Córdoba
- Argentina
- Departamento de Química Teórica y Computacional
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19
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Ilawe NV, Oviedo MB, Wong BM. Correction to Real-Time Quantum Dynamics of Long-Range Electronic Excitation Transfer in Plasmonic Nanoantennas. J Chem Theory Comput 2017; 13:6433. [PMID: 29155584 DOI: 10.1021/acs.jctc.7b01150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Douglas-Gallardo OA, Soldano GJ, Mariscal MM, Sánchez CG. Effects of oxidation on the plasmonic properties of aluminum nanoclusters. NANOSCALE 2017; 9:17471-17480. [PMID: 29106431 DOI: 10.1039/c7nr04904h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The scouting of alternative plasmonic materials able to enhance and extend the optical properties of noble metal nanostructures is on the rise. Aluminum is endowed with a set of interesting properties which turn it into an attractive plasmonic material. Here we present the optical and electronic features of different aluminum nanostructures stemming from a multilevel computational study. Molecular Dynamics (MD) simulations using a reactive force field (ReaxFF), carefully validated with Density Functional Theory (DFT), were employed to mimic the oxidation of icosahedral aluminum nanoclusters. Resulting structures with different oxidation degrees were then studied through the Time-Dependent Density Functional Tight Binding (TD-DFTB) method. A similar approach was used in aluminum nanoclusters with a disordered structure to study how the loss of crystallinity affects the optical properties. To the best of our knowledge, this is the first report that addresses this issue from the fully atomistic time-dependent approach by means of two different and powerful simulation tools able to describe quantum and physicochemical properties associated with nanostructured particles.
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Affiliation(s)
- Oscar A Douglas-Gallardo
- INFIQC (UNC-CONICET), Departamento de Qumica Teŕica y Computacional, Facultad de Ciencias Qumicas, Universidad Nacional de Cŕdoba, Medina Allende y Haya de la Torre, Ciudad Universitaria, Cŕdoba, X5000HUA Cŕdoba, Argentina.
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21
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Bonafé FP, Aradi B, Guan M, Douglas-Gallardo OA, Lian C, Meng S, Frauenheim T, Sánchez CG. Plasmon-driven sub-picosecond breathing of metal nanoparticles. NANOSCALE 2017; 9:12391-12397. [PMID: 28829098 DOI: 10.1039/c7nr04536k] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We present the first real-time atomistic simulation on the quantum dynamics of icosahedral silver nanoparticles under strong laser pulses, using time dependent density functional theory (TDDFT) molecular dynamics. We identify the emergence of sub-picosecond breathing-like radial oscillations starting immediately after laser pulse excitation, with increasing amplitude as the field intensity increases. The ultrafast dynamic response of nanoparticles to laser excitation points to a new mechanism other than equilibrium electron-phonon scattering previously assumed, which takes a much longer timescale. A sharp weakening of all bonds during laser excitation is observed, thanks to plasmon damping into excited electrons in anti-bonding states. This sudden weakening of bonds leads to a uniform expansion of the nanoparticles and launches coherent breathing oscillations.
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Affiliation(s)
- Franco P Bonafé
- INFIQC (CONICET - Universidad Nacional de Córdoba), Departamento de Química Teórica y Computacional, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
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22
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Negre CFA, Mniszewski SM, Cawkwell MJ, Bock N, Wall ME, Niklasson AMN. Recursive Factorization of the Inverse Overlap Matrix in Linear-Scaling Quantum Molecular Dynamics Simulations. J Chem Theory Comput 2016; 12:3063-73. [DOI: 10.1021/acs.jctc.6b00154] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christian F. A. Negre
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Susan M. Mniszewski
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Marc J. Cawkwell
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Nicolas Bock
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Michael E. Wall
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Anders M. N. Niklasson
- Theoretical Division and ‡Computer, Computational, and Statistical Sciences
Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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23
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Mansilla Wettstein C, Bonafé FP, Oviedo MB, Sánchez CG. Optical properties of graphene nanoflakes: Shape matters. J Chem Phys 2016; 144:224305. [DOI: 10.1063/1.4953172] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Candela Mansilla Wettstein
- Instituto de Investigaciones Fisicoquímicas de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET), Departamento de Matemática y Física, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - Franco P. Bonafé
- Instituto de Investigaciones Fisicoquímicas de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET), Departamento de Matemática y Física, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba X5000HUA, Argentina
| | - M. Belén Oviedo
- Department of Chemical & Environmental Engineering and Materials Science and Engineering Program, University of California, Riverside, California 92521, USA
| | - Cristián G. Sánchez
- Instituto de Investigaciones Fisicoquímicas de Córdoba, Consejo Nacional de Investigaciones Científicas y Técnicas (INFIQC - CONICET), Departamento de Matemática y Física, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba X5000HUA, Argentina
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24
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Oviedo MB, Wong BM. Real-Time Quantum Dynamics Reveals Complex, Many-Body Interactions in Solvated Nanodroplets. J Chem Theory Comput 2016; 12:1862-71. [PMID: 26918732 DOI: 10.1021/acs.jctc.5b01019] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Electronic excitations in the liquid phase are surprisingly rich and considerably more complex than either gas-phase or solid-state systems. While the majority of physical and biological processes take place in solvent, our understanding of nonequilibrium excited-state processes in these condensed phase environments remains far from complete. A central and long-standing issue in these solvated environments is the assessment of many-body interactions, particularly when the entire system is out of equilibrium and many quantum states participate in the overall process. Here we present a microscopic picture of solute-solvent electron dynamics and solvatochromic effects, which we uncover using a new real-time quantum dynamics approach for extremely large solvated nanodroplets. In particular, we find that a complex interplay of quantum interactions underlies our observations of solute-solvent effects, and simple macroscopic solvatochromic shifts can even be qualitatively different at the microscopic molecular level in these systems. By treating both the solvent and the solute on the same footing at a quantum-mechanical level, we demonstrate that the electron dynamics in these systems are surprisingly complex, and the emergence of many-body interactions underlies the dynamics in these solvated systems.
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Affiliation(s)
- M Belén Oviedo
- Department of Chemical & Environmental Engineering and Materials Science & Engineering Program, University of California, Riverside , Riverside, California 92521, United States
| | - Bryan M Wong
- Department of Chemical & Environmental Engineering and Materials Science & Engineering Program, University of California, Riverside , Riverside, California 92521, United States
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25
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Medrano CR, Oviedo MB, Sánchez CG. Photoinduced charge-transfer dynamics simulations in noncovalently bonded molecular aggregates. Phys Chem Chem Phys 2016; 18:14840-9. [DOI: 10.1039/c6cp00231e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Real-time atomistic simulation of photoexcited exciton dynamics in non-covalently bonded perylene diimide aggregates.
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Affiliation(s)
- Carlos R. Medrano
- Departamento de Matemática y Física
- Facultad de Ciencias Químicas
- INFIQC
- Universidad Nacional de Córdoba
- Ciudad Universitaria
| | - M. Belén Oviedo
- Department of Chemical & Environmental Engineering and Materials
- Science and Engineering Program
- University of California
- Riverside
- USA
| | - Cristián G. Sánchez
- Departamento de Matemática y Física
- Facultad de Ciencias Químicas
- INFIQC
- Universidad Nacional de Córdoba
- Ciudad Universitaria
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26
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Kosumi D, Nishiguchi T, Sugisaki M, Hashimoto H. Ultrafast coherent spectroscopic investigation on photosynthetic pigment chlorophyll a utilizing 20 fs pulses. J Photochem Photobiol A Chem 2015. [DOI: 10.1016/j.jphotochem.2015.06.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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27
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Negre CFA, Young KJ, Oviedo MB, Allen LJ, Sánchez CG, Jarzembska KN, Benedict JB, Crabtree RH, Coppens P, Brudvig GW, Batista VS. Photoelectrochemical Hole Injection Revealed in Polyoxotitanate Nanocrystals Functionalized with Organic Adsorbates. J Am Chem Soc 2014; 136:16420-9. [DOI: 10.1021/ja509270f] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Christian F. A. Negre
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Karin J. Young
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Ma. Belén Oviedo
- Department
of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Laura J. Allen
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Cristián G. Sánchez
- Departamento
de Matemática y Física, Facultad de Ciencias Químicas,
INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - Katarzyna N. Jarzembska
- Department
of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
- Department
of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warszawa, Poland
| | - Jason B. Benedict
- Department
of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Robert H. Crabtree
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Philip Coppens
- Department
of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Gary W. Brudvig
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department
of Chemistry and Energy Sciences Institute, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, United States
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28
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Primo EN, Oviedo MB, Sánchez CG, Rubianes MD, Rivas GA. Bioelectrochemical sensing of promethazine with bamboo-type multiwalled carbon nanotubes dispersed in calf-thymus double stranded DNA. Bioelectrochemistry 2014; 99:8-16. [DOI: 10.1016/j.bioelechem.2014.05.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 05/03/2014] [Accepted: 05/20/2014] [Indexed: 01/18/2023]
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29
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Morzan UN, Ramírez FF, Oviedo MB, Sánchez CG, Scherlis DA, Lebrero MCG. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework. J Chem Phys 2014; 140:164105. [DOI: 10.1063/1.4871688] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Kosumi D, Nakagawa K, Sakai S, Nagaoka Y, Maruta S, Sugisaki M, Dewa T, Nango M, Hashimoto H. Ultrafast intramolecular relaxation dynamics of Mg- and Zn-bacteriochlorophyll a. J Chem Phys 2014; 139:034311. [PMID: 23883031 DOI: 10.1063/1.4813526] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ultrafast excited-state dynamics of the photosynthetic pigment (Mg-)bacteriochlorophyll a and its Zn-substituted form were investigated by steady-state absorption∕fluorescence and femtosecond pump-probe spectroscopic measurements. The obtained steady-state absorption and fluorescence spectra of bacteriochlorophyll a in solution showed that the central metal compound significantly affects the energy of the Qx state, but has almost no effect on the Qy state. Photo-induced absorption spectra were recorded upon excitation of Mg- and Zn-bacteriochlorophyll a into either their Qx or Qy state. By comparing the kinetic traces of transient absorption, ground-state beaching, and stimulated emission after excitation to the Qx or Qy state, we showed that the Qx state was substantially incorporated in the ultrafast excited-state dynamics of bacteriochlorophyll a. Based on these observations, the lifetime of the Qx state was determined to be 50 and 70 fs for Mg- and Zn-bacteriochlorophyll a, respectively, indicating that the lifetime was influenced by the central metal atom due to the change of the energy gap between the Qx and Qy states.
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Affiliation(s)
- Daisuke Kosumi
- The Osaka City University Advanced Research Institute for Natural Science and Technology, 3-3-138 Sugimoto, Osaka 558-8585, Japan.
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31
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Negre CFA, Perassi EM, Coronado EA, Sánchez CG. Quantum dynamical simulations of local field enhancement in metal nanoparticles. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:125304. [PMID: 23449278 DOI: 10.1088/0953-8984/25/12/125304] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Field enhancements (Γ) around small Ag nanoparticles (NPs) are calculated using a quantum dynamical simulation formalism and the results are compared with electrodynamic simulations using the discrete dipole approximation (DDA) in order to address the important issue of the intrinsic atomistic structure of NPs. Quite remarkably, in both quantum and classical approaches the highest values of Γ are located in the same regions around single NPs. However, by introducing a complete atomistic description of the metallic NPs in optical simulations, a different pattern of the Γ distribution is obtained. Knowing the correct pattern of the Γ distribution around NPs is crucial for understanding the spectroscopic features of molecules inside hot spots. The enhancement produced by surface plasmon coupling is studied by using both approaches in NP dimers for different inter-particle distances. The results show that the trend of the variation of Γ versus inter-particle distance is different for classical and quantum simulations. This difference is explained in terms of a charge transfer mechanism that cannot be obtained with classical electrodynamics. Finally, time dependent distribution of the enhancement factor is simulated by introducing a time dependent field perturbation into the Hamiltonian, allowing an assessment of the localized surface plasmon resonance quantum dynamics.
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Affiliation(s)
- Christian F A Negre
- Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba, Argentina
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32
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Fuertes VC, Negre CFA, Oviedo MB, Bonafé FP, Oliva FY, Sánchez CG. A theoretical study of the optical properties of nanostructured TiO2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:115304. [PMID: 23406993 DOI: 10.1088/0953-8984/25/11/115304] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Optical properties of TiO(2) nanoclusters (with more than 30 TiO(2) units) were calculated within a fully atomistic quantum dynamic framework. We use a time dependent tight-binding model to describe the electronic structure of TiO(2) nanoclusters in order to compute their optical properties. We present calculated absorption spectra for a series of nanospheres of different radii and crystal structures. Our results show that bare TiO(2) nanoclusters have the same adsorption edge for direct electronic transition independently of the crystal structure and the nanocluster size. We report values of the adsorption edge of around 3.0 eV for all structures analyzed. In the present work we demonstrate that, for small clusters, both the direct transition absorption edge and the blue shifting phenomena are masked by thermal disorder.
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Affiliation(s)
- Valeria C Fuertes
- Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba, Argentina
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33
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Oviedo MB, Zarate X, Negre CFA, Schott E, Arratia-Pérez R, Sánchez CG. Quantum Dynamical Simulations as a Tool for Predicting Photoinjection Mechanisms in Dye-Sensitized TiO2 Solar Cells. J Phys Chem Lett 2012; 3:2548-2555. [PMID: 26295873 DOI: 10.1021/jz300880d] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
On the basis of a time-dependent self-consistent density functional tight-binding (TD-DFTB) approach, we present a novel method able to capture the differences between direct and indirect photoinjection mechanisms in a fully atomistic picture. A model anatase TiO2 nanoparticle (NP) functionalized with different dyes has been chosen as the object of study. We show that a linear dependence of the rate of electron injection with respect to the square of the applied field intensity can be viewed as a signature of a direct electron injection mechanism. In addition, we show that the nature of the photoabsorption process can be understood in terms of orbital population dynamics occurring during photoabsorption. Dyes involved in both direct (type-I) and indirect (type-II) mechanisms were studied to test the predictive power of this method.
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Affiliation(s)
- M Belén Oviedo
- †Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Ximena Zarate
- ‡Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, República 275, Santiago, Chile
| | - Christian F A Negre
- †Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Eduardo Schott
- ‡Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, República 275, Santiago, Chile
| | - Ramiro Arratia-Pérez
- ‡Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, República 275, Santiago, Chile
| | - Cristián G Sánchez
- †Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
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34
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Oviedo MB, Sánchez CG. Transition Dipole Moments of the Qy Band in Photosynthetic Pigments. J Phys Chem A 2011; 115:12280-5. [DOI: 10.1021/jp203826q] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- M. Belén Oviedo
- Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Cristián G. Sánchez
- Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
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