Investigação Do Solvatocromismo E Ionocromismo Do Corante Azul Do Nilo Através Das Espectroscopias Raman, Infravermelho E Uv-Vis

Abstract

SOLVATOCHROMISM AND IONOCHROMISM OF THE NILE BLUE DYE A THROUGH RAMAN, INFRARED AND UV-VIS SPECTROSCOPIES. The present work presents the systematic study of Nile Blue A (NB) dye, a cationic textile dye, through electronic and vibrational spectroscopies (Raman, resonant Raman scatter and infrared absorption) in the presence of distinct anions (chloride, bromide, perchlorate and sulfate) and protic and aprotic solvents of different polarities (water, ethanol, acetone, acetonitrile, chloroform and ethyl acetate). There were vibrational changes resulting from the formation and destruction of aggregates according to the chemical environment, besides the formation of a molecular conformation with higher energy in apolar aprotic solvents.

Early synthetic textile dyes of the late 19th century from the “Primo Levi” Chemistry Museum (Rome): A multi-technique analytical investigation

“…S2 Supporting Information), with four methyl instead of two ethyl groups. Comparing the Raman bands observed for this sample and those reported in the literature for Nile Blue, only a partial correspondence is found with the FT-Raman spectrum of the historical reference sample discussed in [8] , while a more complete similarity is detected with the modern sample examined in [45] . In this scenario, interesting results were provided by SERS analysis: the main peaks in the spectrum ( Fig.…”