Light-induced degradation dynamics in realgar: in situ structural investigation using single-crystal X-ray diffraction study and X-ray photoelectron spectroscopy

Kyono, Atsushi

doi:10.2138/am.2005.1785

Cited by 58 publications

(41 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…4 As 4 S 5 þ 2 As 2 O 3 . The hypothesis that oxygen plays an important role in the light-induced alteration of arsenic sulfides was recently supported by X-ray photoelectron spectroscopic measurements of light-exposed realgar reported by Kyono et al (2005). These authors also reported the structural data of a crystal of realgar exposed to light and hypothesized that also in the case of realgar the increase of the unit-cell volume is caused by the partial replacement of As 4 S 4 molecules by As 4 S 5 molecules.…”

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 80%

“…On the other hand, a general effect of weakening of intermolecular contacts should result in an isotropic increase of the unit-cell volume. On the contrary, the expansion of the unit cell of realgar appears considerably anisotropic Kyono et al, 2005); a and c sin b increase linearly whereas b remains substantially unchanged. As noted by Kyono et al, there are two positions alone for additional S atom to form As--S--As linkage on available As--As edges in the realgar-type molecules, on the edges crossed by their 4 axis.…”

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 93%

“…In spite of the ingenuity of the model, however, no evidence for the change of S positions resulted from their structural refinements and the molecular parameters (sphericity and volume) remain fairly constant during exposure. The continuous increase of the unit-cell volume observed for realgar, therefore, was ascribed to the variation of the intermolecular distances (Kyono et al, 2005). Indeed, if the volume of the As 4 unit is a reliable parameter to estimate the molecular sulfur content (see 3.1. paragraph), at least a slight increment of V(As 4 ) should be observed as a function of exposure times.…”

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 97%

“…These authors also reported the structural data of a crystal of realgar exposed to light and hypothesized that also in the case of realgar the increase of the unit-cell volume is caused by the partial replacement of As 4 S 4 molecules by As 4 S 5 molecules. According to the model elaborated by Kyono et al (2005), additional sulfur would be incorporated to produce As 4 S 5 molecules, and then released by breaking a As--S--As linkage to form As 4 S 4 molecules (pararealgar-type). The process could cyclically continue by re-attachment of the free S to another As 4 S 4 (realgar-type).…”

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 99%

“…Roberts et al (1980) first clarified that the friable, yellow film commonly covering realgar consists of pararealgar and not orpiment as previously proposed. Since that time, many studies have focused on the effects of the exposure of realgar or other arsenic sulfides to light, starting from the detailed study of Douglass et al (1992) up to the recent investigations by single-crystal (Kyono et al, 2005;Bonazzi et al, 2006) and powder X-ray diffraction (Ballirano and Maras, 2006 …”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

A crystallographic review of arsenic sulfides: effects of chemical variations and changes induced by exposure to light

Bonazzi¹,

Bindi²

2008

Zeitschrift Für Kristallographie - Crystalline Materials

View full text Add to dashboard Cite

Crystal data for natural and synthetic arsenic sulfides are reported and discussed. Most of them [a-and b-dimorphite, realgar, b-As 4 S 4 phase, pararealgar, Kutoglu's As 4 S 4 (II) phase, alacranite, uzonite, orthorhombic As 4 S 5 phase] have a crystal structure consisting of a packing of cage-like, covalently bonded As 4 S n (n ¼ 3, 4 and 5) molecules held together by weak interactions of van der Waals character. Their structures are compared in terms of molecular packing and molecular parameters. The layered structural arrangement of orpiment, As 2 S 3 , is described and the effects of the incorporation of Se replacing for S is discussed. The structures of wakabayashilite and getchellite, which contain mixed (As, Sb) coordination polyhedra, are also described to outline the geometric effects of the Sb ! As substitution. The results of recent studies dealing with the effects of the exposure of realgar or other arsenic sulfides to visible light are reported and discussed. Their interest in the study of arsenical pigments and their preservation in artwork is outlined with some examples of application.

show abstract

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 80%

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 93%

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 97%

Section: Light-induced Alteration 41 Progresses In the Knowledge Of mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A crystallographic review of arsenic sulfides: effects of chemical variations and changes induced by exposure to light

Bonazzi¹,

Bindi²

2008

Zeitschrift Für Kristallographie - Crystalline Materials

View full text Add to dashboard Cite

show abstract

Photoinduced effects of monochromatic visible light with different wavelengths on realgar

Zhang

et al. 2022

J Raman Spectroscopy

View full text Add to dashboard Cite

Realgar is a well-known light-sensitive material. Under illumination, realgar is oxidized into arsenolite and uzonite, and uzonite generates pararealgar. To further study the effect of light with different wavelengths on realgar, herein, the light-induced reaction of realgar under irradiation of four monochromatic visible lights, red light (628.0-648.0 nm), amber light (585.4-604.6 nm), green light (506.0-544.0 nm), and blue light (428.9-447.1 nm), have been studied by confocal Raman, X-ray diffraction, and ultraviolet-visible absorption spectroscopy. The results of Raman spectra show that the photoinduced effect of different monochromatic lights on realgar is different. Realgar is stable under red light but is sensitive to other visible lights like amber, green, and blue light.The light-induced reaction of realgar is the fastest under the green light. The effect of the blue light on realgar is complicated. Pararealgar, as the lightinduced product of realgar, transforms into uzonite under the blue light, which is discussed based on the bandgap of pararealgar calculated using the density functional theory method.

show abstract

A noninvasive complementary study of an Egyptian polychrome cartonnage pigments using SEM, EPMA, and Raman spectroscopy

Gard

Santos²,

Daizo

et al. 2020

Surface & Interface Analysis

View full text Add to dashboard Cite

Raman spectroscopy, optical microscopy, scanning electron microscopy (SEM), and electron probe microanalysis (EPMA) were used to study pigments on an Egyptian cartonnage from the Ptolemaic period (305-30 BC). The surface morphology of each color region was examined using backscattering (BS) and secondary electron imaging. SEM X-ray energy dispersive spectrometry and EPMA wavelength dispersive spectroscopy provided semiquantitative chemical analysis of each pigment. Raman spectroscopy was used to identify the minerals associated with the pigments. This technique confirmed the presence of cinnabar (α-HgS) in the red part of the fragments. A mixture of orpiment (As 2 S 3) and bonazziite (β-As 4 S 4) and/or alacránite (As 8 S 9) was detected in the yellow regions of the fragments. The orange pigment was confirmed to be a mixture of orpiment, uzonite (χ-As 4 S 5), and pararealgar (As 4 S 4). Egyptian blue (CaCuSi 4 O 10) and Egyptian green ((Cu,Ca)SiO 3) pigments were detected from blue/green dark-colored regions of the fragments.

show abstract

Light-induced degradation dynamics in realgar: in situ structural investigation using single-crystal X-ray diffraction study and X-ray photoelectron spectroscopy

Cited by 58 publications

References 15 publications

A crystallographic review of arsenic sulfides: effects of chemical variations and changes induced by exposure to light

A crystallographic review of arsenic sulfides: effects of chemical variations and changes induced by exposure to light

Photoinduced effects of monochromatic visible light with different wavelengths on realgar

A noninvasive complementary study of an Egyptian polychrome cartonnage pigments using SEM, EPMA, and Raman spectroscopy

Contact Info

Product

Resources

About