Sara Valadas, Peter Vandenabeele, Milene Gil, José C. Frade, Eva Vermeersch, Sylvia Lycke, Luís Dias, António Candeias, Mafalda Costa
{"title":"Analysis of green pigments: The case of Almada Negreiros maritime station murals in Lisbon (Portugal)","authors":"Sara Valadas, Peter Vandenabeele, Milene Gil, José C. Frade, Eva Vermeersch, Sylvia Lycke, Luís Dias, António Candeias, Mafalda Costa","doi":"10.1002/jrs.6717","DOIUrl":null,"url":null,"abstract":"In 1949, Almada Negreiros painted at the maritime station of Rocha do Conde de Óbidos, in Lisbon, six monumental mural paintings, which are considered as his highest artistic achievement. On these paintings, he resorted to a bright colourful palette, which needs to be studied to support conservation and preservation of these artworks for future generations. Among the pigments under study within project ALMADA, the identification of the green samples is the most challenging, as Almada Negreiros seems to have explored different hues by using simultaneously inorganic (e.g., emerald green, Scheele's green and viridian) as well as organo‐synthetic pigments that were rather unusual when employing a traditional mural painting technique (e.g., PG7 and PG8). Moreover, he seems to have admixed white (e.g., titanium white) or blue pigments (e.g., ultramarine) to modify the hues. The different colourants found, as well as the use of mixtures of pigments, hints that Almada Negreiros was keen on experimenting and applying relatively novel painting materials. Raman spectroscopy, given its ability to identify inorganic as well as organic components, is a key analytical tool to discriminate between all these compounds. The findings were also supported by complimentary analytical techniques, including colourimetry, handheld X‐ray fluorescence spectroscopy (h‐XRF) and micro‐Fourier‐transform infrared spectroscopy (μ‐FT‐IR). Identification of the green pigments by Raman spectroscopy is, however, not always straightforward, and it is demonstrated how changes in relative band intensities and band broadening can point to mixtures, where the Raman spectral features of some compounds can easily be overseen in the spectrum.","PeriodicalId":16926,"journal":{"name":"Journal of Raman Spectroscopy","volume":null,"pages":null},"PeriodicalIF":2.4000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Raman Spectroscopy","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1002/jrs.6717","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"SPECTROSCOPY","Score":null,"Total":0}
引用次数: 0
Abstract
In 1949, Almada Negreiros painted at the maritime station of Rocha do Conde de Óbidos, in Lisbon, six monumental mural paintings, which are considered as his highest artistic achievement. On these paintings, he resorted to a bright colourful palette, which needs to be studied to support conservation and preservation of these artworks for future generations. Among the pigments under study within project ALMADA, the identification of the green samples is the most challenging, as Almada Negreiros seems to have explored different hues by using simultaneously inorganic (e.g., emerald green, Scheele's green and viridian) as well as organo‐synthetic pigments that were rather unusual when employing a traditional mural painting technique (e.g., PG7 and PG8). Moreover, he seems to have admixed white (e.g., titanium white) or blue pigments (e.g., ultramarine) to modify the hues. The different colourants found, as well as the use of mixtures of pigments, hints that Almada Negreiros was keen on experimenting and applying relatively novel painting materials. Raman spectroscopy, given its ability to identify inorganic as well as organic components, is a key analytical tool to discriminate between all these compounds. The findings were also supported by complimentary analytical techniques, including colourimetry, handheld X‐ray fluorescence spectroscopy (h‐XRF) and micro‐Fourier‐transform infrared spectroscopy (μ‐FT‐IR). Identification of the green pigments by Raman spectroscopy is, however, not always straightforward, and it is demonstrated how changes in relative band intensities and band broadening can point to mixtures, where the Raman spectral features of some compounds can easily be overseen in the spectrum.
期刊介绍:
The Journal of Raman Spectroscopy is an international journal dedicated to the publication of original research at the cutting edge of all areas of science and technology related to Raman spectroscopy. The journal seeks to be the central forum for documenting the evolution of the broadly-defined field of Raman spectroscopy that includes an increasing number of rapidly developing techniques and an ever-widening array of interdisciplinary applications.
Such topics include time-resolved, coherent and non-linear Raman spectroscopies, nanostructure-based surface-enhanced and tip-enhanced Raman spectroscopies of molecules, resonance Raman to investigate the structure-function relationships and dynamics of biological molecules, linear and nonlinear Raman imaging and microscopy, biomedical applications of Raman, theoretical formalism and advances in quantum computational methodology of all forms of Raman scattering, Raman spectroscopy in archaeology and art, advances in remote Raman sensing and industrial applications, and Raman optical activity of all classes of chiral molecules.