title: A vibrational spectroscopic and principal component analysis of triarylmethane dyes by comparative laboratory and portable instrumentation.
abstract: This contribution examines the utility of vibrational spectroscopy by bench and portable Raman/surface enhanced Raman and infrared methods for the investigation of ten early triarlymethane dye powder references and dye solutions applied on paper. The complementary information afforded by the techniques is shown to play a key role in the identification of specific spectral marker ranges to distiguish early synthetic dyes of art-historical interest through the elaboration of an in-house database of modern organic dyes. Chemometric analysis has permitted a separation of data by the discrimination of di-phenyl-naphthalenes and triphenylmethanes (di-amino and tri-amino derivatives). This work serves as a prelude to the validation of a non-invasive working method for in situ characterization of these synthetic dyes through a careful comparison of respective strengths and limitations of each portable technique.
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari (CNR-ISTM), c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy. Electronic address: b.bd.doherty@talk21.com.
authors.forename: B
authors.initials: B
authors.lastname: Doherty
authors.affiliation: Associazione Laboratorio di Diagnostica di Spoleto, piazza Campello 2, 06049 Spoleto, PG, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Vagnini
authors.affiliation: Conservation Science, Heritage Conservation and Commemoration Directorate, Parks Canada, 1800 Walkley Rd., Ottawa, ON K1A 0M5, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Dufourmantelle
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari (CNR-ISTM), c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Centro di eccellenza, SMAArt (Scientific Methodologies applied to Archaeology and Art), c/o Dipartimento di Chimica, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sgamellotti
authors.affiliation: Centro di eccellenza, SMAArt (Scientific Methodologies applied to Archaeology and Art), c/o Dipartimento di Chimica, Università degli Studi di Perugia, Perugia, Italy; Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Brunetti
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari (CNR-ISTM), c/o Dipartimento di Chimica, Università degli Studi di Perugia, via Elce di Sotto 8, I-06123 Perugia, Italy; Centro di eccellenza, SMAArt (Scientific Methodologies applied to Archaeology and Art), c/o Dipartimento di Chimica, Università degli Studi di Perugia, Perugia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Miliani
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004396:Coloring Agents / Q000737:chemistry*; D007753:Laboratories; D010209:Paper; D025341:Principal Component Analysis; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014320:Triphenylmethyl Compounds / Q000737:chemistry*; D014732:Vibration
chemical_list: D004396:Coloring Agents; D014320:Triphenylmethyl Compounds
keywords: Mid-infrared spectroscopy; Portable instrumentation; Principal component analysis; Surface enhanced Raman spectroscopy; Triarylmethane dyes