The Application of a New FTIR Microspectroscopy Accessory for Far-IR Analysis of Artists Pigments

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1 The Application of a New FTIR Microspectroscopy Accessory for Far-IR Analysis of Artists Pigments David W. Schiering 1, Ron Rubinovitz 2, Anthony W. Didomenico 1, Beth Price 3, and Kate Duffy 3 1. Czitek, 6 Finance Dr., Danbury, CT Thermo Fisher Scientific, 4410 Lottsford Vista Road Lanham, MD, Philadelphia Museum of Art, PO Box 7646, Philadelphia, PA FTIR Spectroscopy for the Study of Material Culture Harvard University Boston University May 6-7, 2017

2 SurveyIR FTIR Microspectroscopy Presentation Outline SurveyIR System Overview Features & Specifications Optical Description Application Inorganic Pigments in Art Work SurveyIR 2017 Czitek, LLC 2

3 SurveyIR FTIR Microspectroscopy Accessory System Overview Sample compartment mounted user installed USB Powered Transmission, reflection, and oblique illumination modes IR reflection, ATR, and transmission modes Variable remote image mask in IR mode espot Video Imaging Software control Manual coarse/fine focus adjust Manual transmission condenser focus adjust Accommodates variety of sample mounts and cells Simultaneous Sample Viewing/IR Spectrum Collection Equal Optical Efficiency in Infrared R/T modes (without compromise) SurveyIR Czitek

4 espot Video Microscopy Software SurveyIR 2017 Czitek, LLC 4

5 High Quality Images: Transmission, Reflectance & Oblique Illumination Modes Nylon Fiber in compression cell Mica SurveyIR 2017 Czitek, LLC

6 Far-IR Spectroscopy (Terahertz Spectroscopy) Near IR μm (12, cm -1 ) Overtones and Combination Bands Mid IR um ( cm -1 ) Fundamental Molecular Vibrations Far-IR μm ( cm -1 ) ( THz) Vibrations Involving Large Atoms, Lattice Modes Bands observed in the Far-IR involve motions that include halogen stretching, aromatic ring bending, skeletal bending, hydrogen bond stretching, torsional modes, lattice vibrations, and motions involving large (massive) atoms. Analytical applications of Far IR spectroscopy are sparse. Competing / complimentary technologies for pigments XRD, XFR, EDAX, Raman, PLM Traditional solid sample preparation methods include polyethylene (PE) pellets or Nujol Mulls supported between PE windows. Experimental challenges for Far IR microspectroscopy are relatively low radiance of thermal sources, relatively low responsivity of room temperature detectors, reduction of throughput by sample defining mask, signal loss due to diffraction (long wavelengths), and sample-related effects. SurveyIR 2017 Czitek, LLC 6

7 Experimental Setup Thermo Fisher Scientific is50 FT-IR Spectrometer Czitek SurveyIR FTIR Microspectroscopy Accessory Everglo Source Instrument Mounted Detector(s): PE DTGS, KBr DTGS, MCT Automatic BS Interchange: KBr, Solid Substrate Dry Air (N 2 ) Purge SurveyIR as setup in PMA Scientific Laboratory 8 cm -1 Resolution, Happ Genzel Apodization SurveyIR 2017 Czitek, LLC 7

8 Reflectance Surface Characterization - Diamond ATR of Printed Paperboard Unprinted Kaolinite + CaCO 3 Printed ATR survey Wavenumber (cm -1 ) ATR contact SurveyIR 2017 Czitek, LLC 8

9 %T %T Far-IR Diamond ATR of Coated Paperboard CaCO cm cm cm -1 Al 2 O 3 2SiO 2 2H 2 O 350 cm cm cm Solid State BS, PE, and Diamond Optics, DTGS detector MCT Cutoff, 700 cm -1 DTGS KBr Cutoff, 400 cm KBr and Diamond Optics, DTGS detector Wavenumbers (cm -1 ) SurveyIR 2017 Czitek, LLC

10 Qing Dynasty Lacquer Clothes Wardrobe Provenance: China, Asia Date: 18th Century Period: Qing Dynasty ( ) Size: Height: (290.2 cm), Width: (143.5 cm), Depth: (66.8 cm) Philadelphia Museum of Art, Acc. #

11 Decorative Surfaces Cross-section of Lacquer from interior Two Campaigns Red & yellow Layers were analyzed.

12 Binder & Pigments PY-GCMS detected catechol markers for urushiol Urushiol Toxicodendron vernicifluum, China, Korea & Japan Laccol Toxicodendron succedaneum, Vietnam & Taiwan Thitsiol Gluta usitata, Burma &Thailand

13 %T %T Red Pigment: Vermilion Red Lacquer Layer Diamond ATR HgS 343 cm cm cm Forbes Pigment Collection Vermilion (Cinnabar, HgS) Pigment Diamond ATR Wavenumbers (cm -1 ) Appl Spectrosc, 23, 219 (1969), J Chem Phys, 52, 4090 (1970) SurveyIR 2017 Czitek, LLC 13

14 %T %T Yellow Pigment: Orpiment Yellow Lacquer Layer Low E Glass Refl (250 μm) Ag 2 S cm cm cm cm cm Forbes Pigment Collection Orpiment (Ag 2 S 3 ) Pigment Low E Glass Refl (250 μm) Wavenumbers (cm -1 ) Am. Mineralogist, 54, 1062 (1969) SurveyIR 2017 Czitek, LLC 14

15 %T %T Titanium White Golden Heavy Body Acrylics Titanium White Diamond ATR TiO cm cm cm Wavenumbers (cm-1) SurveyIR 2017 Czitek, LLC 15

16 %T %T Zinc White Golden Heavy Body Acrylics Zinc White Diamond ATR ZnO 380 cm Wavenumbers (cm -1 ) SurveyIR 2017 Czitek, LLC 16

17 Log 1/R High Density Polyethylene Table Cloth Mid-IR/Far-IR diamond ATR Glittering Gold High Density PE film by Diamond ATR in Far-IR Inorganic Filler Glittering Gold PE film by Diamond ATR in mid-ir Wavenumbers (cm -1 ) SurveyIR 2017 Czitek, LLC 17

18 Far-IR Spectroscopy of Cultural Materials Anal Bioanal Chem, 408, 3373 (2016) Spectrochim Acta A, 75, 1061 (2010) K Fukunaga, THz Technology Applied to Cultural Heritage in Practice, Springer, Japan, (2016) R A Nyquist & R O Kagel, Infrared Spectra of Inorganic Compounds ( cm-1), Academic Press, New York, (1971). SurveyIR 2017 Czitek, LLC 18

19 Conclusions New Technology Allows the Collection of Far-IR spectra of microsamples Mid-IR and Far-IR using the same spectrometer Binder, fillers, pigments Transmission, Reflection, and ATR modes High Mass Inorganic Pigments Cost-effective solution SurveyIR 2017 Czitek, LLC 19

20 International Outreach: Sharing High-Quality IR & Raman Reference Data IRUG. org is a publicly accessible, web-enabled database disseminating peer-reviewed FTIR & Raman reference spectra to scientists, conservators, students, & educators. The collaborative initiative engages over 150 institutions worldwide.