25th Anniversary Article: Design of Polymethine Dyes for All‐Optical Switching Applications: Guidance from Theoretical and Computational Studies

Abstract

All-optical switching--controlling light with light--has the potential to meet the ever-increasing demand for data transmission bandwidth. The development of organic π-conjugated molecular materials with the requisite properties for all-optical switching applications has long proven to be a significant challenge. However, recent advances demonstrate that polymethine dyes have the potential to meet the necessary requirements. In this review, we explore the theoretical underpinnings that guide the design of π-conjugated materials for all-optical switching applications. We underline, from a computational chemistry standpoint, the relationships among chemical structure, electronic structure, and optical properties that make polymethines such promising materials.

Fine Structure in Electronic Spectra of Cyanine Dyes: Are Sub‐Bands Largely Determined by a Dominant Vibration or a Collection of Singly Excited Vibrations?

“…Consequently many quantitative calculations concerning dyes which incorporated the effect of Duschinsky rotation were performed, whose modus operandi are consistent with the conclusion that “…the shoulders are not determined by a unique, dominant, vibrational normal mode but rather by a collection of singly excited vibrations.”…”

Photo‐isomerization of the Cyanine Dye Alexa‐Fluor 647 (AF‐647) in the Context of dSTORM Super‐Resolution Microscopy

“…Numerous quantum chemical procedures have been applied to compute structures for cyanine dyes. [92] Such compounds are ideal modelsf or testing linear,f ree-electront reatments [93] and for assessing the reliability of computerm ethods for calculating optical spectra. [94] Calculations have also been used to predict likely structures for cyanine-based photo-isomers, [95] including ones similart oA F-647.…”

Large Optical Nonlinearity Induced by Singlet Fission in Pentacene Films

“…[1][2][3][4][5][6][7][8][9][10][11][12] Lately,o rganic-molecule-basedn onlinear optical (NLO) materials have attracted much attention. [1][2][3][4][5][6][7][8][9][10][11][12] Lately,o rganic-molecule-basedn onlinear optical (NLO) materials have attracted much attention.…”

“…Them easured magnitude of c (3) approaches to about 10 À9 esu which is among the largest third-order susceptibility reported in organic molecules. [7,11] One of the potential applications of such large SF-induced optical nonlinearity is further confirmed by demonstrating an optically induced polarization rotation.…”