Symmetric anionic polymethine dyes derived from fluorene and its derivatives with electron-acceptor substituents: synthesis and spectral properties

Molecular design of near infrared polymethine dyes: A review

“…Matichak et al [89], M. Halik [90], J.M. Hales et al [91], I. Kurdyukova et al [92,93] . Theoretical consideration of the electron structure of dioxaborine anionic dyes was performed by J. Fabian and H. Hartmann [94].…”

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

“…Some structural changes to the end groups, however, can dramatically change the electronic and optical properties. In cyanines with fluorene‐based end groups, the end groups introduce additional OPA and TPA excited states close in energy to state e , which has a pronounced effect on the NLO response . In addition, adding bulky substituents to the end groups can induce torsion along the polymethine bridge; when the twisting appreciably disrupts the conjugation and localizes the frontier MOs on one part of the molecule, the NLO response is then strongly altered …”

Electrochemical and energetic characteristics of new dye-sensitizers for photovoltaic cells

“…The former dyes relate to the anionic type [16][17][18]20 and the latter onesto the intraionic merocyanines. 22 All PDs 1-6 reveal multiple light absorption bands 18,20,21 while the \classical" PDs show only a single band. 23 Multiple bands are due to various types of electron transfer involving different energy levels of the nitro groups participating in the general -conjugation system.…”

“…23 Multiple bands are due to various types of electron transfer involving different energy levels of the nitro groups participating in the general -conjugation system. [16][17][18]20 A variable length of the polymethine chain of all the dyes is a strong structural factor for both types of PD, and lengthening of this chain is seen 23 as the main tool to synthesize new useful deeply colored dyes.…”