Equilibrium and Structural Study of m-Methyl Red in Aqueous Solutions: Distribution Diagram Construction

Thermal response and thermochromism of methyl red-based copolymer systems – coupled responsiveness in critical solution behaviour and optical absorption properties

“…ESI Table S 2). 23,24,78,79 In the ortho-isomer (ΔpK a 0.14), the difference between the parent compound and the derivative is small and may be explained with the change in solvent. This difference, however, increases with the acidity of the isomer (para: ΔpK a 0.25; meta: ΔpK a 0.45).…”

Comparison of photoinduced reorientation ofortho-,meta-, andpara-methyl red-doped nematic liquid crystals on rubbed polyimide

“…10 -12, indicate that the dyes exist in equilibrium mixtures of the anionic and the neutral forms. For all three dyes, the optical absorbance of the anionic form occurs between 425 and 450 nm and has a smaller cross-section than the optical absorbance of the neutral form, which occurs between 525 and 550 nm 29,30 . These spectra indicate that the anionic form of the dye is dominant in the meta and para dye doped nematics.…”

Effect of Azo Compounds on the Structure and Mechanical Properties of a Copper Coating Electrodeposited on Oxidized Aluminum Alloys

“…The addition of an aqueous solution of a copper salt to the system leads to the gradual disappearance of the absorption band at λ max ~ 428 nm and the appearance of a band at λ max 523 nm and a characteristic shoulder in the region of 550-560 nm. Simultaneously with the above processes, an intense deepening of the color (pink-lilac color of the solution) and an increase in the absorption intensity occur [51].…”

“…It can be stated that the interaction of copper(II) with azo dyes, in particular, MR, is poorly understood [34][35][36][37][38]. There are some published data on the effect of various components, for example, surfactants, on the complexation of Cu(II) with azo dyes [39][40][41][42].…”