Electronic excitations and first hyperpolarizability of 2-methyl-4-nitroaniline clusters

Maxime Guillaume, Edith Botek, Benoit Champagne, Frédéric Castet, L. Ducasse

Research output: Contribution to journalArticle

Abstract

The crystal packing effects upon the static and dynamic first hyperpolarizability of 2-methyl-4-nitroaniline (MNA) clusters have been addressed at the TDHF/AM1 level. Due to electrostatic interactions, in 1-D arrays of MNA unit cells extending along the a crystallographic axis, the effective hyperpolarizability strongly increases whereas stacking unit cells along the b or c axes leads to a reduction of these quantities. These effects are magnified in the case of frequency-dependent quantifies. The first hyperpolarizability variations can mostly be related to bathochromatic and hypsochromatic shifts as well as to changes in transition dipole moments of the low-energy excited states that dominate the UV/visible absorption spectra. From calculations performed at the CIS/INDO/S level of approximation, these dominant excited states present an important intramolecular charge transfer character and bathochromatic (hypsochromatic) shifts are associated with increase (decrease) of the transition dipole moments. In addition, a large number of intermolecular charge-transfer excited states have been detected. In the small MNA aggregates as well as in clusters extending only along the b or c crystallographic axes, these excited states possess small transition dipole moments. On the other hand, when stacking MNA unit cells along the a axis the electrostatic interactions induce a decrease of the excitation energies and an increase of the transition dipole moments of these intermolecular charge transfer states. As a consequence, they account for a nonnegligible contribution to the first hyperpolarizability.

Original languageEnglish
Pages (from-to)1378-1387
Number of pages10
JournalInternational Journal of Quantum Chemistry
Volume90
Issue number4-5
DOIs
Publication statusPublished - 15 Nov 2002

Fingerprint

Dipole moment
Excited states
Electron transitions
Charge transfer
dipole moments
Coulomb interactions
electronics
excitation
charge transfer
cells
Excitation energy
electrostatics
Commonwealth of Independent States
shift
Absorption spectra
visible spectrum
Crystals
4-nitroaniline
interactions
absorption spectra

Keywords

  • 2-methyl-4-nitroaniline
  • Charge transfer
  • Electronic excitation energies
  • First hyperpolarizability
  • Molecular crystal

Cite this

@article{0157b01643a045708094a1251904fac2,
title = "Electronic excitations and first hyperpolarizability of 2-methyl-4-nitroaniline clusters",
abstract = "The crystal packing effects upon the static and dynamic first hyperpolarizability of 2-methyl-4-nitroaniline (MNA) clusters have been addressed at the TDHF/AM1 level. Due to electrostatic interactions, in 1-D arrays of MNA unit cells extending along the a crystallographic axis, the effective hyperpolarizability strongly increases whereas stacking unit cells along the b or c axes leads to a reduction of these quantities. These effects are magnified in the case of frequency-dependent quantifies. The first hyperpolarizability variations can mostly be related to bathochromatic and hypsochromatic shifts as well as to changes in transition dipole moments of the low-energy excited states that dominate the UV/visible absorption spectra. From calculations performed at the CIS/INDO/S level of approximation, these dominant excited states present an important intramolecular charge transfer character and bathochromatic (hypsochromatic) shifts are associated with increase (decrease) of the transition dipole moments. In addition, a large number of intermolecular charge-transfer excited states have been detected. In the small MNA aggregates as well as in clusters extending only along the b or c crystallographic axes, these excited states possess small transition dipole moments. On the other hand, when stacking MNA unit cells along the a axis the electrostatic interactions induce a decrease of the excitation energies and an increase of the transition dipole moments of these intermolecular charge transfer states. As a consequence, they account for a nonnegligible contribution to the first hyperpolarizability.",
keywords = "2-methyl-4-nitroaniline, Charge transfer, Electronic excitation energies, First hyperpolarizability, Molecular crystal",
author = "Maxime Guillaume and Edith Botek and Benoit Champagne and Fr{\'e}d{\'e}ric Castet and L. Ducasse",
year = "2002",
month = "11",
day = "15",
doi = "10.1002/qua.10355",
language = "English",
volume = "90",
pages = "1378--1387",
journal = "International Journal of Quantum Chemistry",
issn = "0020-7608",
publisher = "John Wiley and Sons Inc.",
number = "4-5",

}

Electronic excitations and first hyperpolarizability of 2-methyl-4-nitroaniline clusters. / Guillaume, Maxime; Botek, Edith; Champagne, Benoit; Castet, Frédéric; Ducasse, L.

In: International Journal of Quantum Chemistry, Vol. 90, No. 4-5, 15.11.2002, p. 1378-1387.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Electronic excitations and first hyperpolarizability of 2-methyl-4-nitroaniline clusters

AU - Guillaume, Maxime

AU - Botek, Edith

AU - Champagne, Benoit

AU - Castet, Frédéric

AU - Ducasse, L.

PY - 2002/11/15

Y1 - 2002/11/15

N2 - The crystal packing effects upon the static and dynamic first hyperpolarizability of 2-methyl-4-nitroaniline (MNA) clusters have been addressed at the TDHF/AM1 level. Due to electrostatic interactions, in 1-D arrays of MNA unit cells extending along the a crystallographic axis, the effective hyperpolarizability strongly increases whereas stacking unit cells along the b or c axes leads to a reduction of these quantities. These effects are magnified in the case of frequency-dependent quantifies. The first hyperpolarizability variations can mostly be related to bathochromatic and hypsochromatic shifts as well as to changes in transition dipole moments of the low-energy excited states that dominate the UV/visible absorption spectra. From calculations performed at the CIS/INDO/S level of approximation, these dominant excited states present an important intramolecular charge transfer character and bathochromatic (hypsochromatic) shifts are associated with increase (decrease) of the transition dipole moments. In addition, a large number of intermolecular charge-transfer excited states have been detected. In the small MNA aggregates as well as in clusters extending only along the b or c crystallographic axes, these excited states possess small transition dipole moments. On the other hand, when stacking MNA unit cells along the a axis the electrostatic interactions induce a decrease of the excitation energies and an increase of the transition dipole moments of these intermolecular charge transfer states. As a consequence, they account for a nonnegligible contribution to the first hyperpolarizability.

AB - The crystal packing effects upon the static and dynamic first hyperpolarizability of 2-methyl-4-nitroaniline (MNA) clusters have been addressed at the TDHF/AM1 level. Due to electrostatic interactions, in 1-D arrays of MNA unit cells extending along the a crystallographic axis, the effective hyperpolarizability strongly increases whereas stacking unit cells along the b or c axes leads to a reduction of these quantities. These effects are magnified in the case of frequency-dependent quantifies. The first hyperpolarizability variations can mostly be related to bathochromatic and hypsochromatic shifts as well as to changes in transition dipole moments of the low-energy excited states that dominate the UV/visible absorption spectra. From calculations performed at the CIS/INDO/S level of approximation, these dominant excited states present an important intramolecular charge transfer character and bathochromatic (hypsochromatic) shifts are associated with increase (decrease) of the transition dipole moments. In addition, a large number of intermolecular charge-transfer excited states have been detected. In the small MNA aggregates as well as in clusters extending only along the b or c crystallographic axes, these excited states possess small transition dipole moments. On the other hand, when stacking MNA unit cells along the a axis the electrostatic interactions induce a decrease of the excitation energies and an increase of the transition dipole moments of these intermolecular charge transfer states. As a consequence, they account for a nonnegligible contribution to the first hyperpolarizability.

KW - 2-methyl-4-nitroaniline

KW - Charge transfer

KW - Electronic excitation energies

KW - First hyperpolarizability

KW - Molecular crystal

UR - http://www.scopus.com/inward/record.url?scp=0037112308&partnerID=8YFLogxK

U2 - 10.1002/qua.10355

DO - 10.1002/qua.10355

M3 - Article

VL - 90

SP - 1378

EP - 1387

JO - International Journal of Quantum Chemistry

JF - International Journal of Quantum Chemistry

SN - 0020-7608

IS - 4-5

ER -