Elsevier

Journal of Crystal Growth

Volume 312, Issue 23, 15 November 2010, Pages 3490-3492
Journal of Crystal Growth

Growth and Raman spectroscopic characterization of As4S4 (II) single crystals

https://doi.org/10.1016/j.jcrysgro.2010.09.001Get rights and content

Abstract

As described by Kutoglu (1976 [16]), single crystals of As4S4 (II) phase have been grown using a new two-step synthesis that drastically increases the reproducibility that is attainable in synthetic experiments. First, through photo-induced phase transformation, pararealgar powder is prepared as a precursor instead of AsS melt. Then it is dissolved and recrystallized from CS2 solvent. Results show that single crystals of the As4S4 (II) phase were obtained reproducibly through the dissolution–recrystallization process. Single crystals of As4S4 (II) obtained using this method were translucent and showed a uniform yellow-orange color. The crystal exhibits a platelet-like shape as a thin film with well-developed faces (0 1 0) and (0  0). The grown crystals are as large as 0.50×0.50×0.01 mm. They were characterized using powder and single crystal X-ray diffraction techniques to confirm the phase identification and the lattice parameters. The As4S4 (II) phase crystallizes in monoclinic system with cell parameters a=11.202(4) Å, b=9.954(4) Å, c=7.142(4) Å, β=92.81(4)°, V=795.4(6) Å3, which shows good agreement with the former value. Raman spectroscopic studies elucidated the behavior of the substance and the relation among phases of tetra-arsenic tetrasulfide.

Introduction

Investigations of photochemical sensitivity in arsenic chalcogenides are important for fundamental sciences and for their practical applications in optical memories, optical switches, and fiber lasers. Tetra-arsenic tetrasulfide, As4S4, exists in four crystalline modifications. Many studies have been conducted on their crystal structures, spectroscopic properties, phase transitions, and stability fields of the As4S4 polymorphs: realgar (α-As4S4) [1], [2], [3], [4], [5], [6]; the high-temperature phase (β-As4S4) based on the same realgar-type molecule with different molecular packing [7], [8], [9], [10], [11], [12], [13]; pararealgar obtained by photo-induced phase transformation of both the realgar and the high-temperature phases [14], [15]; and As4S4 (II) phase, composed of the pararealgar-type molecule with different molecular arrangements [16]. The summary of crystal structural information is shown in Table 1. Because of the unique effect induced by photoexcitation, which is analogous to a domino effect [17], numerous studies have been made to date on the photo-induced phase transition from realgar-type molecule to pararealgar molecule [18], [19], [20], [21], [22], [23], [24], [25], [26], [27].

Although many studies have examined α-As4S4, β-As4S4, and pararealgar, very little information about the As4S4 (II) phase is available. Single crystals of the As4S4 (II) phase are synthesized by recrystallizing a quenched AsS melt from 500 to 600 °C [16]. To date, this is the only report describing the crystallization and structural characterization by X-ray diffraction analysis of this phase. Although Kutoglu [16] documented conditions under which As4S4 (II) phase single crystals have been grown, we have never obtained the crystals using this method. In the past thirty years, no reported study has examined the structure and optical properties of the As4S4 (II) phase.

This study is intended to reveal an appropriate crystal growth method of the As4S4 (II) phase. This paper reports the growth of As4S4 (II) single crystals by recrystallization of the pararealgar from CS2 solution. The crystals were subsequently characterized using powder and single crystal X-ray diffraction analyses. For this study, the Raman spectra of the As4S4 (II) phase were first measured on the flat surface of the single crystal under ambient conditions.

Section snippets

Experimental and results

According to Kutoglu [16], single crystals of As4S4 (II) phase were obtained from a quenched AsS melt as a starting substance. The method documented in the previous study [16] was attempted to synthesize As4S4 (II) single crystals, but the crystals were never obtained. The structure of As4S4 (II) phase comprises pararealgar-type molecules held together by van der Waals forces, which suggests that the pararealgar possessing the same molecular configuration is more effective as a precursor than

Summary

Single crystals of As4S4 (II) phase were grown using the dissolution–recrystallization method. No impurity phase was formed using this crystal growth method. Crystals obtained using this method exhibit a platelet-like form with well-developed faces (0 1 0) and (0  0) with a size of several hundred micrometers square. The largest crystals were approximately 1 mm×1 mm×0.02 mm. As determined from X-ray diffraction analyses, the single crystals prepared in this study are highly homogeneous. This simple

Acknowledgments

This work was supported by a Grant-in-Aid for Young Scientists (B) (No. 19740325) from the Japan Society for the Promotion of Science. An anonymous reviewer is kindly acknowledged for improving the quality of the manuscript.

References (28)

  • L.T. Bryndzia et al.

    J. Chem. Thermodyn.

    (1988)
  • M. Muniz-Miranda et al.

    Spectrochim. Acta

    (1996)
  • H.A. Bullen et al.

    Surf. Sci.

    (2003)
  • T. Ito et al.

    Acta Crystallogr.

    (1952)
  • I.N. Penkov et al.

    Dokl. Akad. Nauk SSSR

    (1963)
  • R. Forneris

    Am. Mineral.

    (1969)
  • D.J.E. Mullen et al.

    Z. Kristallogr.

    (1972)
  • W. Bues et al.

    Z. Anorg. Allg. Chem.

    (1983)
  • A.H. Clark

    Am. Mineral.

    (1970)
  • B.G. Street et al.

    J. Inorg. Nucl. Chem.

    (1970)
  • E.J. Porter et al.

    J. Am. Chem. Soc. Dalton Trans.

    (1972)
  • G.W. Roland

    Can. Mineral.

    (1972)
  • S.C. Yu et al.

    Am. Mineral.

    (1972)
  • P.C. Burns et al.

    Can. Mineral.

    (2001)
  • Cited by (0)

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