### Abstract

To understand the large nonlinear optical activities of azobenzene dendrons, which are dendritic macromolecules comprising donor-acceptor azobenzenes as branching units, we carried out ab initio calculations for azobenzene monomers, i.e., 4-dimethylamino-4′-carboxyazobenzene and 4-dimethylamino-2′-nitro-4′-carboxyazobenzene, and their dimers. We determined the stable structures and calculated the first hyperpolarizabilities, using the coupled-perturbed Hartree-Fock method. We found that two azobenzenes in the stable structure of each of the dimers have correlated orientations that produce a large overall dipole. The hyperpolarizabilities for the dimers were larger than those for the corresponding monomers. From these findings, we conclude that the poling of branching units by the interaction between azobenzene moieties within the azobenzene dendrons results in cone-shape structures that cause the large nonlinear optical activities.

Original language | English |
---|---|

Pages (from-to) | 83-90 |

Number of pages | 8 |

Journal | Molecular Crystals and Liquid Crystals Science and Technology Section B: Nonlinear Optics |

Volume | 26 |

Issue number | 1-3 |

Publication status | Published - Dec 1 2000 |

Externally published | Yes |

Event | International Workshop on Molecular Design of Photonic Materials - Takarazuka, Japan Duration: Dec 9 1999 → Dec 10 1999 |

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### All Science Journal Classification (ASJC) codes

- Control and Systems Engineering
- Condensed Matter Physics

### Cite this

*Molecular Crystals and Liquid Crystals Science and Technology Section B: Nonlinear Optics*,

*26*(1-3), 83-90.

**Ab initio calculations of first hyperpolarizabilities for donor-acceptor azobenzenes and their dimers.** / Okuno, Y.; Yokoyama, Shiyoshi; Mashiko, S.

Research output: Contribution to journal › Conference article

*Molecular Crystals and Liquid Crystals Science and Technology Section B: Nonlinear Optics*, vol. 26, no. 1-3, pp. 83-90.

}

TY - JOUR

T1 - Ab initio calculations of first hyperpolarizabilities for donor-acceptor azobenzenes and their dimers

AU - Okuno, Y.

AU - Yokoyama, Shiyoshi

AU - Mashiko, S.

PY - 2000/12/1

Y1 - 2000/12/1

N2 - To understand the large nonlinear optical activities of azobenzene dendrons, which are dendritic macromolecules comprising donor-acceptor azobenzenes as branching units, we carried out ab initio calculations for azobenzene monomers, i.e., 4-dimethylamino-4′-carboxyazobenzene and 4-dimethylamino-2′-nitro-4′-carboxyazobenzene, and their dimers. We determined the stable structures and calculated the first hyperpolarizabilities, using the coupled-perturbed Hartree-Fock method. We found that two azobenzenes in the stable structure of each of the dimers have correlated orientations that produce a large overall dipole. The hyperpolarizabilities for the dimers were larger than those for the corresponding monomers. From these findings, we conclude that the poling of branching units by the interaction between azobenzene moieties within the azobenzene dendrons results in cone-shape structures that cause the large nonlinear optical activities.

AB - To understand the large nonlinear optical activities of azobenzene dendrons, which are dendritic macromolecules comprising donor-acceptor azobenzenes as branching units, we carried out ab initio calculations for azobenzene monomers, i.e., 4-dimethylamino-4′-carboxyazobenzene and 4-dimethylamino-2′-nitro-4′-carboxyazobenzene, and their dimers. We determined the stable structures and calculated the first hyperpolarizabilities, using the coupled-perturbed Hartree-Fock method. We found that two azobenzenes in the stable structure of each of the dimers have correlated orientations that produce a large overall dipole. The hyperpolarizabilities for the dimers were larger than those for the corresponding monomers. From these findings, we conclude that the poling of branching units by the interaction between azobenzene moieties within the azobenzene dendrons results in cone-shape structures that cause the large nonlinear optical activities.

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M3 - Conference article

AN - SCOPUS:0034438679

VL - 26

SP - 83

EP - 90

JO - Nonlinear Optics Quantum Optics

JF - Nonlinear Optics Quantum Optics

SN - 1543-0537

IS - 1-3

ER -