1. Spectroscopic techniques for the characterization of organic and inorganic materials in modern art: a case study Francesca Rosi 1, Alessia Daveri 1, Costanza Miliani 2, Brunetto Giovanni Brunetti 1, Antonio Sgamellotti 1,2 1 Dip. di Chimica, Università di Perugia, Via Elce di Sotto, 8, Perugia, 06123 (PG) - ITALY 2 Dip. di Chimica, CNR c/o Università di Perugia, Via Elce di Sotto, 8, Perugia, 06123 (PG) - ITALY Sezione Tematica INSTM: 1. Materiali inorganici cristallini ed amorfi

2. The study of materials and techniques of contemporary art the employ of new materials and not well codified techniques having at disposal a large variety of new materials and also the license to use them with unconventional execution techniques The intrinsic complexity of modern artworks The necessity to characterize materials and methods for preserving the conservation state and start correct conservation procedures Project PRIN2006: Development of specific methodologies for the non-invasive study of materials and techniques of contemporary art

3. Calamita Cosmica enormous sculpture representing a human skeleton dimensions 24x6x10 m 3 Gino De Dominicis (1947-1998) www.repubblica.it Mole Vanvitelliana, Ancona 2005 Piazzetta Reale, Milano 2007

4. Micro destructive spectroscopic techniques Leica DM R Optical Microscope (OM) equipped with a digital camera Leica DC300 SEM-EDS Electron scanning microscope Philips XL30 with an LaB6source and an energy dispersive X-ray EDAX/DX4 detector. Epoxy resin (Epofix, Struers) was used for the preparation of cross-sections JASCO Ventuno micro-Raman (  R): - 1200 and 2400 mm/lines gratings - CCD detector cooled at –50°C; - Confocal OM (5x, 20x, 50x, 100x). - Nd:YAG laser (532 nm); - spectral resolution of about 2 cm -1 JASCO FTIR 470-plus spectrophotometer Micro-FTIR (  FTIR): -nitrogen cooled mercury cadmium telluride detector (MCT) -IRT-30 optical microscope -reflectance transmittance geometry (Cassegrain 16x/32x objectives)

5. Diffuse reflection can cause distortion of the band intensities as compared to transmission spectra, and specular reflection may cause derivative or inverted band shape. transmittance Mapping  FTIR measurement molecular distribution in the stratigraphy 16x Cassegrain objective; map dimension 250x550  m 2 ; x,y step 50  m ; total time 13 h Scans 800; spectral resolution 4 cm -1 specular 0°/0° geometry Reflectance  FTIR technique diffuse

6. The enormous sculpture is mainly composed by polystyrene (EPS) Gypsum has been found as filler Materials characterization

7. Stratigraphic study 1 2 3 4 5 1.White layer of variable thickness 2.light brown layer 260-395  m 3.brass lamina 80-230  m 4.white layer 100-150  m 5.white layer 790-900  m OM imageBSE-SEM image

8. 1 & 2 inner layers  elemental composition: Si, Al, Ca, Fe, Ti inorganic components  CaCO 3 : 1 + 3 @ 2500 cm -1 ; 1 + 4 @ 1800 cm -1   -SiO 2 : (  -SiO 2 ) @ 1100 cm -1 ; +  (  - SiO 2 ) @ 1800;1870; 1980 cm -1 organic components

9. 3. Brass lamina Cu, Zn brass (15% of Zn, similoro brass) analogies with the gold decoration technique of ancient painters Benozzo Gozzoli, S.Girolamo Chapel, Montefalco (1452) Sn Au 80-230  m

10. 4. white layer Elemental composition similar to 1 & 2 layers: Si, Al, Ca, Ti, Mg Talc is a hydrated magnesium silicate with the chemical formula Mg 3 Si 4 O 10 (OH) 2 Organic molecular patterns with carbonyl ester @ 1750 cm -1 100-150  m

11. 5. white finish layer Elemental composition: Si and Ti as main elements L. Burgio, R. J. H. Clark, Kournal of Raman Spectroscopy, 31, 395–401 (2000) 790-900  m

12. Micro FT-IR mapping experiments Area of the 1 + 3 combination band @ 2428-2638 cm -1 CaCO 3 distribution CaCO 3 is mainly distributed in layers 4, 1 & 2, it is absent in the external white layer

13. Micro FT-IR mapping experiments Organic compounds distribution Shift of the carbonyl stretching from 1730- 1750 cm -1

14. Micro FT-IR mapping experiments Polystyrene distribution CH signal @ 3013-3095 cm -1

15. 1 2 3 4 5 Allumino silicate matrix with CaCO 3, SiO 2, TiO 2, Fe-oxides; oilresin 1750 cm -1 carbonyl Cu, Zn lamina Allumino silicate matrix with CaCO 3, SiO 2, TiO 2, Fe-oxides, talc; 1750 cm -1 carbonyl Polystyrene mixed with SiO 2, TiO 2, talc, ftalo dyes; 1740 cm -1 carbonyl Stratigraphic study

16. Calamita Cosmica Conservation polystyrene substrata external painted layers: difference in mechanical properties; salt crystallization; aging of external vinyl resin www.repubblica.it

17. NA WD 32x 0.7 10mm 16x 0.57 20.5mm