Synthesis and nonlinear optical properties of organic supermolecular chromophores based on porphyrinic and metal polypyridyl components / Animesh Nayak.

Format:

Book

Manuscript

Thesis/Dissertation

Author/Creator:

Nayak, Animesh.

Contributor:

Therien, Michael J., advisor.

University of Pennsylvania.

Language:

English

Subjects (All):

Penn dissertations--Chemistry.

Chemistry--Penn dissertations.

Local Subjects:

Penn dissertations--Chemistry.

Chemistry--Penn dissertations.

Physical Description:

xxii, 290 pages : illustrations (some color) ; 29 cm

Production:

2011.

Summary:

For the last several years, there has been increasing interest in developing non-linear optical (NLO) materials derived from organic molecules because of wide application of NLO materials in telecommunications, data storage, sensor protection and imaging. Porphyrin-based chromophores that possess the most spectacular hyperpolarizabilities delineated to date feature (porphinato)zinc(II) (PZn) and metal(II)polypyridyl (M) units connected via an ethyne bridge. This work demonstrates the synthesis and opto-electronic studies of new series of MPZn based chromophores that feature large hyperpolarizabilities (beta HRS) at telecommunication relevant wavelengths. These chromophores are made in high yields from respective precursor complexes by palladium catalyzed cross coupling reactions. Octopolar donor-acceptor-donor (D-A-D) type of chromophores based on MPZn structure exhibited large betaHRS at 1500 nm which is an important telecommunication relevant wavelength. It has been demonstrated that by modulating the position of different electronic absorption bands, beta HRS values can also be manipulated for wavelength specific NLO response. Another new series of chromophores that have been designed from inverse designed based calculation that incorporate proquinoidal spacer moiety into MPZn framework shows tremendously large calculated beta0 values. Indeed, it has been demonstrated that MPZn type chromphores featuring proquinoidal spacer exhibit large betaHRS values at 1500 nm. Thomas-Kuhn-sum over states (TKS) calculations have been performed to rationalize and explain dispersion of hyperpolarizability and depolarization ratio. TKS extract effective excited state-to-excited state transition dipole terms in a few effective state formalism from experimental linear-absorption spectra and thereby estimate frequency dependent hyperpolarizabilities that include both two and three-level contributions. Besides large measured hyperpolarizabilities, supermolecular sensitized NIR-to-visible photon upconversion has been demonstrated for the first time with MPZn based supermolecular sensitizer and peryline diimide acceptor. Analogous studies utilizing tetracene as the acceptor/annihilator establish a new record anti-Stokes shift of 0.86 eV for sensitized TTA.

Notes:

Adviser: Michael J. Therien.

Thesis (Ph.D. in Chemistry) -- University of Pennsylvania, 2011.

Includes bibliographical references.