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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on As2S3 by Materials Project

As2S3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two As2S3 sheets oriented in the (0, 1, 0) direction. there are two inequivalent As3+ sites. In the first As3+ site, As3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.31 Å. In the second As3+ site, As3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are two shorter (2.29 Å) and one longer (2.30 Å) As–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in an L-shaped geometry to two As3+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two As3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on As2S3 by Materials Project

As2S3 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two As2S3 sheets oriented in the (0, 0, 1) direction. there are four inequivalent As3+ sites. In the first As3+ site, As3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. All As–S bond lengths are 2.30 Å. In the second As3+ site, As3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.30 Å. In the third As3+ site, As3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.30 Å. In the fourth As3+ site, As3+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are one shorter (2.29 Å) and two longer (2.30 Å) As–S bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the fifth S2- site, S2- is bonded in a water-like geometry to two As3+ atoms. In the sixth S2- site, S2- is bonded in a water-like geometry to two As3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on As2S3(NF6)2 by Materials Project

N2S3(AsF6)2 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of eight AsF6 clusters and four N2S3 clusters. In each AsF6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.76–1.81 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In each N2S3 cluster, N4+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.55 Å) and one longer (1.61 Å) N–S bond length. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to two equivalent N4+ atoms. In the second S2- site, S2- is bonded in a distorted single-bond geometry to one N4+ atom. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one N4+ atom. The S–N bond length is 1.55 Å.

36 MATERIALS SCIENCE↗
NASA NTRS1981

Evaporated As2S3 Luneburg lenses for LiNbO3:Ti optical waveguides

Luneburg lenses of good quality were formed on high index optical waveguides by evaporation of arsenic trisulfide glass through simple masks. Using only two thin circular aperture masks, lenses with focal spots of a few times the diffraction limited width at f/4 were obtained. These lenses were designed for and tested at both visible (633 nm) and infrared wavelengths. Procedures for the design, fabrication, and testing of lenses of this type are described.

Busch, J. R.↗
NASA NTRS1982

Design, fabrication and evaluation of chalcogenide glass Luneburg lenses for LiNbO3 integrated optical devices

Optical waveguide Luneburg lenses of arsenic trisulfide glass are described. The lenses are formed by thermal evaporation of As2S3 through suitably placed masks onto the surface of LiNbO3:Ti indiffused waveguides. The lenses are designed for input apertures up to 1 cm and for speeds of f/5 or better. They are designed to focus the TM sub 0 guided mode of a beam of wavelength, external to the guide, of 633 nm. The refractive index of the As2S3 films and the changes induced in the refractive index by exposure to short wavelength light were measured. Some correlation between film thickness and optical properties was noted. The short wavelength photosensitivity was used to shorten the lens focal length from the as deposited value. Lenses of rectangular shape, as viewed from above the guide, as well as conventional circular Luneburg lenses, were made. Measurements made on the lenses include thickness profile, general optical quality, focal length, quality of focal spot, and effect of ultraviolet irradiation on optical properties.

Wood, V. E.↗
NASA NTRS1974

Holography with standing surface plasma waves

Holography with standing surface plasma waves, where both reference and object beams propagate in opposite directions, has been investigated using an Al reflection grating coated with evaporated As2S3 layers. The image, which appears only for p-polarization and at certain critical angles, is enhanced by the Lippman-Bragg effect and by an increase in intensity over ordinary holography approximately equal to the absolute value of the real part of the dielectric constant for Al. Also considered is holography with object light alone in photoresist layers, using the beam-splitting properties of the grating.

Cowan, J. J.↗
NASA NTRS1976

Space processing of chalcogenide glass

The manner in which the weightless, containerless nature of in-space processing can be successfully utilized to improve the quality of infrared transmitting chalcogenide glasses was investigated. The following conclusions were reached: (1) Laboratory experiments have established the techniques, processes and equipment necessary for the production of high purity chalcogenide glasses. (2) Processing techniques have been successfully adopted for Ge28Sb12Se60 glass in a 1-g environment. (3) The Ge28Sb12Se60 glasses that have been processed have optical transmission around 63% (5 mm thick). (4) Laboratory experiments have established that the use of precursor materials in powdered form increases the oxygen contamination of the processed glass. This indicates that high purity precursor materials in bar or pellet form should be used. (5) Modifications were made on the MSFC acoustic levitator in an attempt to improve levitation stability during long-time experiments. Room temperature experiments on As2S3 glasses and high temperature experiments on polystyrene were conducted.

Ali, M. A.↗
NASA NTRS1977

Space processing of chalcogenide glass

The manner in which the weightless, containerless nature of in-space processing can be successfully utilized to improve the quality of infrared transmitting chalcogenide glasses is determined. The technique of space processing chalcogenide glass was developed, and the process and equipment necessary to do so was defined. Earthbound processing experiments with As2S3 and G28Sb12Se60 glasses were experimented with. Incorporated into these experiments is the use of an acoustic levitation device.

Larsen, D. C.↗
NASA NTRS1981

Far infrared filters for the Galileo-Jupiter and other missions

Progress in the development of FIR multilayer interference filters for the net flux radiometer and photopolarizing radiometer to be carried on board the Galileo mission to Jupiter is reported. The multilayer interference technique has been extended to the region above 40 microns by the use of PbTe/II-VI materials in hard-coated combination, with the thickest layers composed of CdSe QWOT at 74 microns and PbTe QWOT. Improvements have also been obtained in filters below 20 microns on the basis of the Chebyshev stack design. A composite filter cutting on steeply at 40 microns has been designed which employs a thin crystal quartz substrate, shorter wavelength absorption in ZnS and As2S3 thin films, and supplementary multilayer interference. Finally, absorptive filters have been developed based on II-VI compounds in multilayer combination with KRS-5 (or 6) on a KRS-5 (or 6) substrate

Seeley, J. S.↗
NASA NTRS1983

Rectangular Luneburg-type lenses for integrated optics

Compact Luneburg-type lenses of rectangular outline as viewed from above have been made by thermal evaporation of As2S3 glass onto single-mode LiNbO3:Ti waveguides through suitably shaped masks and subsequent exposure of the glass to ultraviolet light. The best lenses had speeds of f/5.5 at an aperture of 10 mm and focal spots at reduced aperture about 1.2 times the diffraction-limited size. These lenses have a field of view of at least 25 degrees inside the waveguide.

Wood, V. E.↗