Study of linear and nonlinear optical properties of dendrimers using density matrix renormalization group method

Mukhopadhyay, S and Ramasesha, S (2009) Study of linear and nonlinear optical properties of dendrimers using density matrix renormalization group method. In: Journal of Chemical Physics, 131 (7).

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Abstract

We have used the density matrix renormalization group (DMRG) method to study the linear and nonlinear optical responses of first generation nitrogen based dendrimers with donor acceptor groups. We have employed Pariser–Parr–Pople Hamiltonian to model the interacting pi electrons in these systems. Within the DMRG method we have used an innovative scheme to target excited states with large transition dipole to the ground state. This method reproduces exact optical gaps and polarization in systems where exact diagonalization of the Hamiltonian is possible. We have used a correction vector method which tacitly takes into account the contribution of all excited states, to obtain the ground state polarizibility, first hyperpolarizibility, and two photon absorption cross sections. We find that the lowest optical excitations as well as the lowest excited triplet states are localized. It is interesting to note that the first hyperpolarizibility saturates more rapidly with system size compared to linear polarizibility unlike that of linear polyenes.

Item Type:	Journal Article
Publication:	Journal of Chemical Physics
Publisher:	American Institute of Physics
Additional Information:	Copyright of this article belongs to American Institute of Physics.
Keywords:	excited states;molecule-photon collisions;nonlinear optics; organic compounds;polarisability;PPP calculations; renormalisation. two-photon spectra
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	15 Dec 2009 09:51
Last Modified:	19 Sep 2010 05:45
URI:	http://eprints.iisc.ac.in/id/eprint/23273

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