Konstitution und Farbe von Alizarin‐ und Purpurin‐Farblacken

Abstract

The colour of madder dyes used as pigment in antiquity and in the last centuries is produced mainly by metal complexes of alizarin (1) and purpurin (2). Single crystals of aluminium calcium alizarinate and purpurinate are obtained by twophase crystallization. X-ray structure determinations show tetranuclear complex molecules with four alizarins which are

Absorption and luminescence spectra of cochineal

“…Indeed, the lowest energy electronic transition is of the ππ* type. It is attributed to the conjugated double bonds, but it is characterized by a significant CT contribution [11,12]. CT involves a shift of electron density from the phenolic donor to the quinoid acceptor groups.…”

DFT calculations of the IR and Raman spectra of anthraquinone dyes and lakes

“…The structure of the aluminum/calcium complexes (the lakes) has been determined by X‐ray measurements only in the case of alizarin and purpurin . The alizarin complex is the main component of madder lake, and the structure is made up by four ligand units, as shown in Figure a.…”

Study of Interaction Between Lu(III)–ARS Complex and Herring Sperm DNA

“…ARS can form deeply colored metal complexes. [11] In this study, we synthesized a rare earth metal (Lu) and ARS complex and then focused on the interaction mechanism of Lu(ARS) 3 and DNA. We expected the results to indicate that it is significant in the field of rare earth complexes chemistry and biological inorganic chemistry, [12,13] and provide reference for expanding the application areas of ARS.…”