Solvatochromic and Single Crystal Studies of Two Neutral Triarylmethane Dyes with a Quinone Methide Structure

Abstract

Abstract:The crystal structure of two neutral triarylmethane dyes with a p-quinone methide core was determined by X-ray diffraction analysis. The spectroscopic characteristics of both compounds in 23 solvents with different polarities or hydrogen-bonding donor (HBD) abilities has been studied as a function of three solvatochromic parameters (E T (30), π* and α). Both compounds 1 and 2 showed a pronounced bathochromic shift of the main absorption band on increasing solvent polarity and HBD ability. The correlation is better for compound 2 than for compound 1. The stronger effect and better correlation was observed for compound 2 with the increment of the solvent HBD ability (α parameter).

Heterogeneous Scattering Solvatochromism in Single Prussian Blue Nanoparticles

“…To better describe this scattering solvatochromism, we statistically analyze the solvatochromic shift of the scattering peaks of PBNPs by using several solvent parameters, including the solvent polarity factor [ E T (30)], the dielectric parameter, the polarity parameter, solvent power, and the π* parameter. − Among these solvent parameters, the plot of the scattering peak against E T (30) shows a good linear correlation, as depicted in Figure c. Nevertheless, other solvent parameters cannot be effectively applied to describe the scattering solvatochromism of PBNPs (Figure S14), revealing that unlike the traditional molecular solvatochromic probes, the H-bonding and dipole–dipole interactions are not responsible for the scattering solvatochromism of PBNPs …”