Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “CS2”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ta6Co(CS2)3 by Materials Project

Ta6Co(CS2)3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ta+3.67+ sites. In the first Ta+3.67+ site, Ta+3.67+ is bonded to three C4- and three S2- atoms to form TaC3S3 octahedra that share corners with three TaC3S3 octahedra, corners with three equivalent CoS6 octahedra, and edges with nine TaC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. There are a spread of Ta–C bond distances ranging from 2.22–2.24 Å. There are two shorter (2.51 Å) and one longer (2.52 Å) Ta–S bond lengths. In the second Ta+3.67+ site, Ta+3.67+ is bonded to three C4- and three S2- atoms to form TaC3S3 octahedra that share corners with three TaC3S3 octahedra, edges with nine TaC3S3 octahedra, and a faceface with one CoS6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are one shorter (2.22 Å) and two longer (2.24 Å) Ta–C bond lengths. All Ta–S bond lengths are 2.53 Å. Co2+ is bonded to six S2- atoms to form CoS6 octahedra that share corners with twelve equivalent TaC3S3 octahedra and faces with two equivalent TaC3S3 octahedra. The corner-sharing octahedral tilt angles are 46°. There are two shorter (2.34 Å) and four longer (2.35 Å) Co–S bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.67+ atoms to form CTa6 octahedra that share corners with six STa3Co trigonal pyramids, edges with six equivalent CTa6 octahedra, and edges with six STa3Co trigonal pyramids. In the second C4- site, C4- is bonded to six Ta+3.67+ atoms to form CTa6 octahedra that share corners with six STa3Co trigonal pyramids, edges with six CTa6 octahedra, and edges with six STa3Co trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ta+3.67+ and one Co2+ atom to form distorted STa3Co trigonal pyramids that share corners with three CTa6 octahedra, corners with seven STa3Co trigonal pyramids, edges with three CTa6 octahedra, and edges with two STa3Co trigonal pyramids. The corner-sharing octahedra tilt angles range from 9–11°. In the second S2- site, S2- is bonded to three Ta+3.67+ and one Co2+ atom to form distorted STa3Co trigonal pyramids that share corners with three CTa6 octahedra, corners with seven STa3Co trigonal pyramids, edges with three CTa6 octahedra, and edges with two equivalent STa3Co trigonal pyramids. The corner-sharing octahedra tilt angles range from 9–11°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4Ni(CS2)2 by Materials Project

Nb4Ni(CS2)2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with three equivalent NbC3S3 octahedra, corners with four equivalent NiS6 octahedra, and edges with nine NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. There are one shorter (2.20 Å) and two longer (2.26 Å) Nb–C bond lengths. There are two shorter (2.52 Å) and one longer (2.59 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with two equivalent NiS6 octahedra, corners with three equivalent NbC3S3 octahedra, edges with nine NbC3S3 octahedra, and a faceface with one NiS6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. There are two shorter (2.22 Å) and one longer (2.27 Å) Nb–C bond lengths. There are one shorter (2.52 Å) and two longer (2.57 Å) Nb–S bond lengths. Ni2+ is bonded to six S2- atoms to form NiS6 octahedra that share corners with twelve NbC3S3 octahedra, edges with two equivalent NiS6 octahedra, and faces with two equivalent NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 46–47°. There are two shorter (2.35 Å) and four longer (2.37 Å) Ni–S bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share corners with six equivalent SNb3Ni trigonal pyramids, edges with six CNb6 octahedra, and edges with two equivalent SNb3Ni trigonal pyramids. In the second C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share edges with six CNb6 octahedra and edges with four equivalent SNb3Ni trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Nb+3.50+ and two equivalent Ni2+ atoms. In the second S2- site, S2- is bonded to three Nb+3.50+ and one Ni2+ atom to form distorted SNb3Ni trigonal pyramids that share corners with three equivalent CNb6 octahedra, corners with three equivalent SNb3Ni trigonal pyramids, and edges with three CNb6 octahedra. The corner-sharing octahedral tilt angles are 11°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs2(PSe2)3 by Materials Project

Cs2(PSe2)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 11-coordinate geometry to eleven Se+1.83- atoms. There are a spread of Cs–Se bond distances ranging from 3.82–4.33 Å. In the second Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se+1.83- atoms. There are a spread of Cs–Se bond distances ranging from 3.74–4.28 Å. There are three inequivalent P3+ sites. In the first P3+ site, P3+ is bonded in a water-like geometry to two Se+1.83- atoms. There are one shorter (2.31 Å) and one longer (2.35 Å) P–Se bond lengths. In the second P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three Se+1.83- atoms. There are a spread of P–Se bond distances ranging from 2.15–2.32 Å. In the third P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three Se+1.83- atoms. There are two shorter (2.16 Å) and one longer (2.36 Å) P–Se bond lengths. There are six inequivalent Se+1.83- sites. In the first Se+1.83- site, Se+1.83- is bonded in a distorted single-bond geometry to three Cs1+ and one P3+ atom. In the second Se+1.83- site, Se+1.83- is bonded in an L-shaped geometry to two equivalent Cs1+ and two P3+ atoms. In the third Se+1.83- site, Se+1.83- is bonded in a 1-coordinate geometry to four Cs1+ and one P3+ atom. In the fourth Se+1.83- site, Se+1.83- is bonded in a distorted single-bond geometry to four Cs1+ and one P3+ atom. In the fifth Se+1.83- site, Se+1.83- is bonded in a distorted single-bond geometry to four Cs1+ and one P3+ atom. In the sixth Se+1.83- site, Se+1.83- is bonded in a distorted water-like geometry to two Cs1+ and two P3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs2(B2O3)9 by Materials Project

Cs2(B2O3)9 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Cs sites. In the first Cs site, Cs is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Cs–O bond distances ranging from 3.15–3.61 Å. In the second Cs site, Cs is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of Cs–O bond distances ranging from 3.15–3.61 Å. There are eighteen inequivalent B sites. In the first B site, B is bonded in a bent 120 degrees geometry to two O atoms. There is one shorter (1.38 Å) and one longer (1.40 Å) B–O bond length. In the second B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.39 Å. In the third B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.40 Å. In the fourth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.34–1.40 Å. In the fifth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.33–1.41 Å. In the sixth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.33–1.43 Å. In the seventh B site, B is bonded in a bent 120 degrees geometry to two O atoms. There is one shorter (1.38 Å) and one longer (1.40 Å) B–O bond length. In the eighth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.39 Å. In the ninth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.33–1.41 Å. In the tenth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.33–1.43 Å. In the eleventh B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.36–1.40 Å. In the twelfth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.34–1.40 Å. In the thirteenth B site, B is bonded in a tetrahedral geometry to four O atoms. All B–O bond lengths are 1.48 Å. In the fourteenth B site, B is bonded in a tetrahedral geometry to four O atoms. All B–O bond lengths are 1.49 Å. In the fifteenth B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.34 Å) and two longer (1.39 Å) B–O bond length. In the sixteenth B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.35–1.40 Å. In the seventeenth B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.35 Å) and two longer (1.39 Å) B–O bond length. In the eighteenth B site, B is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.34 Å) and two longer (1.39 Å) B–O bond length. There are twenty-seven inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the second O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two B atoms. In the fourth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the seventh O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the eighth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the ninth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the tenth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the eleventh O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the twelfth O site, O is bonded in a bent 150 degrees geometry to one Cs and two B atoms. In the thirteenth O site, O is bonded in a bent 150 degrees geometry to one Cs and two B atoms. In the fourteenth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the fifteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Cs and two B atoms. In the sixteenth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the seventeenth O site, O is bonded in a distorted bent 120 degrees geometry to one Cs and two B atoms. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the nineteenth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the twentieth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the twenty-first O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the twenty-second O site, O is bonded in a bent 150 degrees geometry to one Cs and two B atoms. In the twenty-third O site, O is bonded in a bent 150 degrees geometry to one Cs and two B atoms. In the twenty-fourth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the twenty-fifth O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the twenty-sixth O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms. In the twenty-seventh O site, O is bonded in a bent 120 degrees geometry to one Cs and two B atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta8Ni(CS2)4 by Materials Project

Ta8Ni(CS2)4 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Ta+3.75+ sites. In the first Ta+3.75+ site, Ta+3.75+ is bonded to three C4- and three S2- atoms to form TaC3S3 octahedra that share corners with two equivalent NiS6 octahedra, corners with three equivalent TaC3S3 octahedra, and edges with nine TaC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. There are two shorter (2.23 Å) and one longer (2.24 Å) Ta–C bond lengths. There are one shorter (2.49 Å) and two longer (2.52 Å) Ta–S bond lengths. In the second Ta+3.75+ site, Ta+3.75+ is bonded to three equivalent C4- and three equivalent S2- atoms to form TaC3S3 octahedra that share corners with three equivalent TaC3S3 octahedra, edges with nine equivalent TaC3S3 octahedra, and a faceface with one NiS6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. All Ta–S bond lengths are 2.53 Å. Ni2+ is bonded to six equivalent S2- atoms to form NiS6 octahedra that share corners with twelve equivalent TaC3S3 octahedra and faces with two equivalent TaC3S3 octahedra. The corner-sharing octahedral tilt angles are 46°. All Ni–S bond lengths are 2.40 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.75+ atoms to form CTa6 octahedra that share corners with six equivalent STa3Ni trigonal pyramids, edges with six CTa6 octahedra, and edges with four equivalent STa3Ni trigonal pyramids. In the second C4- site, C4- is bonded to six equivalent Ta+3.75+ atoms to form CTa6 octahedra that share edges with six equivalent CTa6 octahedra and edges with six equivalent STa3Ni trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ta+3.75+ and one Ni2+ atom to form distorted STa3Ni trigonal pyramids that share corners with three equivalent CTa6 octahedra, corners with five equivalent STa3Ni trigonal pyramids, edges with three CTa6 octahedra, and edges with two equivalent STa3Ni trigonal pyramids. The corner-sharing octahedra tilt angles range from 9–10°. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.75+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnNb4(CS2)2 by Materials Project

Nb4Mn(CS2)2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with three equivalent NbC3S3 octahedra, corners with four equivalent MnS6 octahedra, and edges with nine NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. There are one shorter (2.20 Å) and two longer (2.26 Å) Nb–C bond lengths. There are two shorter (2.54 Å) and one longer (2.59 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with two equivalent MnS6 octahedra, corners with three equivalent NbC3S3 octahedra, edges with nine NbC3S3 octahedra, and a faceface with one MnS6 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. There are two shorter (2.23 Å) and one longer (2.28 Å) Nb–C bond lengths. There are one shorter (2.55 Å) and two longer (2.59 Å) Nb–S bond lengths. Mn2+ is bonded to six S2- atoms to form MnS6 octahedra that share corners with twelve NbC3S3 octahedra, edges with two equivalent MnS6 octahedra, and faces with two equivalent NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 44–48°. There are two shorter (2.46 Å) and four longer (2.50 Å) Mn–S bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share corners with six equivalent SMnNb3 trigonal pyramids, edges with six CNb6 octahedra, and edges with two equivalent SMnNb3 trigonal pyramids. In the second C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share edges with six CNb6 octahedra and edges with four equivalent SMnNb3 trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Nb+3.50+ and two equivalent Mn2+ atoms. In the second S2- site, S2- is bonded to three Nb+3.50+ and one Mn2+ atom to form distorted SMnNb3 trigonal pyramids that share corners with three equivalent CNb6 octahedra, corners with three equivalent SMnNb3 trigonal pyramids, and edges with three CNb6 octahedra. The corner-sharing octahedra tilt angles range from 11–12°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb4Fe(CS2)2 by Materials Project

Nb4Fe(CS2)2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Nb+3.50+ sites. In the first Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with three equivalent NbC3S3 octahedra, corners with four equivalent FeS6 octahedra, and edges with nine NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–46°. There are one shorter (2.23 Å) and two longer (2.25 Å) Nb–C bond lengths. There are two shorter (2.54 Å) and one longer (2.56 Å) Nb–S bond lengths. In the second Nb+3.50+ site, Nb+3.50+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with two equivalent FeS6 octahedra, corners with three equivalent NbC3S3 octahedra, edges with nine NbC3S3 octahedra, and a faceface with one FeS6 octahedra. The corner-sharing octahedra tilt angles range from 0–47°. There are two shorter (2.22 Å) and one longer (2.25 Å) Nb–C bond lengths. There are one shorter (2.55 Å) and two longer (2.58 Å) Nb–S bond lengths. Fe2+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with twelve NbC3S3 octahedra, edges with two equivalent FeS6 octahedra, and faces with two equivalent NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 45–47°. There are two shorter (2.40 Å) and four longer (2.41 Å) Fe–S bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share corners with six equivalent SNb3Fe trigonal pyramids, edges with six CNb6 octahedra, and edges with two equivalent SNb3Fe trigonal pyramids. In the second C4- site, C4- is bonded to six Nb+3.50+ atoms to form CNb6 octahedra that share edges with six CNb6 octahedra and edges with four equivalent SNb3Fe trigonal pyramids. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Nb+3.50+ and two equivalent Fe2+ atoms. In the second S2- site, S2- is bonded to three Nb+3.50+ and one Fe2+ atom to form distorted SNb3Fe trigonal pyramids that share corners with three equivalent CNb6 octahedra, corners with three equivalent SNb3Fe trigonal pyramids, and edges with three CNb6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb6V2(CS2)3 by Materials Project

Nb6V2(CS2)3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Nb3+ sites. In the first Nb3+ site, Nb3+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with three NbC3S3 octahedra, corners with three equivalent VS6 octahedra, edges with nine NbC3S3 octahedra, and a faceface with one VS6 octahedra. The corner-sharing octahedra tilt angles range from 0–48°. There are two shorter (2.22 Å) and one longer (2.23 Å) Nb–C bond lengths. There are a spread of Nb–S bond distances ranging from 2.61–2.63 Å. In the second Nb3+ site, Nb3+ is bonded to three C4- and three S2- atoms to form NbC3S3 octahedra that share corners with three NbC3S3 octahedra, corners with six equivalent VS6 octahedra, and edges with nine NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–45°. There are one shorter (2.22 Å) and two longer (2.23 Å) Nb–C bond lengths. All Nb–S bond lengths are 2.56 Å. V3+ is bonded to six S2- atoms to form VS6 octahedra that share corners with twelve NbC3S3 octahedra, edges with three equivalent VS6 octahedra, and faces with two equivalent NbC3S3 octahedra. The corner-sharing octahedra tilt angles range from 44–48°. There are a spread of V–S bond distances ranging from 2.38–2.41 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six Nb3+ atoms to form edge-sharing CNb6 octahedra. In the second C4- site, C4- is bonded to six Nb3+ atoms to form edge-sharing CNb6 octahedra. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to three Nb3+ and two equivalent V3+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three Nb3+ and two equivalent V3+ atoms.

36 MATERIALS SCIENCE↗
NASA NTRS1975

Brillouin-scattering measurements of the acoustic absorption coefficient in liquid CS2

High-resolution Brillouin spectra were recorded for light scattered at small angles from liquid CS2. The use of a single-mode He-Ne laser, locked in frequency to a Fabry-Perot interferometer, permitted measurements of line widths of the order of 10 MHz for frequencies in the range 300-1000 MHz. These measurements extend previous Brillouin line-width measurements at higher frequencies into the region where relaxation effects are dominant and connect the optical measurements with lower-frequency acoustical data.

Coakley, R. W.↗
NASA NTRS1976

Scattering of high-velocity Ar atoms by CO2, OCS, and CS2

Fast Ar beams have been scattered by room-temperature CO2, OCS, and CS2 to obtain average atom-molecule potentials. The results are consistent with other scattering measurements on similar systems, and are also in excellent agreement with available theoretical calculations based on an electron-gas model. Decomposition of the atom-molecule potentials into constituent atom-atom potentials shows that such a representation can be utilized with fair accuracy but that a definite discrepancy exists.

Amdur, I.↗
NASA NTRS1981

UV studies of electron impact excitation of CS2

The first measurements of emission cross sections of CS2 by electron impact over the wavelength interval 110-510 nm are reported. Absolute emission cross sections are obtained at 100 eV for all spectral features observed in this interval. Emission cross sections as a function of electron energy (0-125 eV) are reported for several of the principal electronic transitions.

Ajello, J. M.↗
NASA NTRS1982

Rate constant for the reaction between OH and CS2 at 298 and 520 K

In an attempt to resolve discrepancies between published values of the rate constant for the reaction between the hydroxyl radical and carbon disulfide, the reaction has been studied in a discharge flow system by using resonance fluorescence for kinetic measurements and mass spectrometry for product analysis. On the basis of the measured rate constant for disappearance of OH, and measurements of the amount of carbonyl sulfide formed, it was estimated that for the reaction HO + CS2 yields HS + OCS, rate constant values are not greater than 3 x 10 to the -15th/cu cm per sec at 520 K and not greater than 7 x 10 to the -15th/cu cm per sec at 298 K, upper limits are specified because of the inability to isolate exclusively this reaction channel, and because of possible involvement of wall reactions. These results confirm the low values found for this rate constant in two very recent studies.

Leu, M.-T.↗
NASA NTRS1982

Photodissociation yields of CS2 at 1060-1520 A

Photoabsorption and fluorescence cross sections of CS2 were measured in the 1060-1520 A region using synchrotron radiation in order to provide information needed for modeling the CS abundance in the interstellar medium. The absorption in the 1060-1200 A region is smooth and continuous, except for the presence of a strong absorption band at 1117 A, while for wavelengths longer than 1200 A, the absorption spectrum shows the structure of Rydberg states. The fluorescence in the 1900-3000 A region begins to appear at 1335 A, and is mainly the CS(A 1Pi-Chi 1Sigma +) transition in the 2400-2800 A region. The fluorescence in the 1900-8000 A region begins to appear at 1490 A, and, in addition to the previous transition, is composed of the transitions of S(1S0-3P1) at 4589 A and of CS(d 3 Delta, a-prime 3Sigma +, and a 3Pi-Chi 1Sigma +) at 3000-4000 A. The quantum yields for the production of fluorescence are determined to have maxima of 13 and 7.5% at 1235 A for the fluorescence in the 1900-8000 and 1900-3000 A regions, respectively.

Day, R. L.↗
NASA NTRS1997

Kinetics and Thermochemistry of Reversible Adduct Formation in the Reaction of Cl((sup 2)P(sub J)) with CS2

Reversible adduct formation in the reaction of Cl((sup 2)P(sub J)) with CS2 has been observed over the temperature range 193-258 K by use of time-resolved resonance fluorescence spectroscopy to follow the decay of pulsed-laser-generated Cl((sup 2)P(sub J)) into equilbrium with CS2Cl. Rate coefficients for CS2Cl formation and decomposition have been determined as a function of temperature and pressure; hence, the equilbrium constant has been determined as a function of temperature. A second-law analysis of the temperature dependence of Kp and heat capacity corrections calculated with use of an assumed CS2Cl structure yields the following thermodynamic parameters for the association reaction: Delta-H(sub 298) = -10.5 +/- 0.5 kcal/mol, Delta-H(sub 0) = -9.5 +/- 0.7 kcal/mol, Delta-S(sub 298) = -26.8 +/- 2.4 cal/mol.deg., and Delta-H(sub f,298)(CS2Cl) = 46.4 +/- 0.6 kcal/mol. The resonance fluorescence detection scheme has been adapted to allow detection of Cl((sup 2)P(sub J)) in the presence of large concentrations of O2, thus allowing the CS2Cl + Cl + O2 reaction to be investigated. We find that the rate coefficient for CS2Cl + O2 reaction via all channels that do not generate Cl((sup 2)P(sub J)) is less than 2.5 x 10(exp-16) cu cm/(molecule.s) at 293 K and 300-Torr total pressure and that the total rate coefficient is less than 2 x 10 (exp -15) cu cm/(molecule.s) at 230 K and 30-Torr total pressure. Evidence for reversible adduct formation in the reaction of Cl((sup 2)P(sub J)) with COS was sought but not observed, even at temperatures as low as 194 K.

Nicovich, J. M.↗
DOE OSTI2023

X-ray induced Coulomb explosion imaging of transient excited-state structural rearrangements in CS2

Abstract Structural imaging of transient excited-state species is a key goal of molecular physics, promising to unveil rich information about the dynamics underpinning photochemical transformations. However, separating the electronic and nuclear contributions to the spectroscopic observables is challenging, and typically requires the application of high-level theory. Here, we employ site-selective ionisation via ultrashort soft X-ray pulses and time-resolved Coulomb explosion imaging to interrogate structural dynamics of the ultraviolet photochemistry of carbon disulfide. This prototypical system exhibits the complex motifs of polyatomic photochemistry, including strong non-adiabatic couplings, vibrational mode couplings, and intersystem crossing. Immediately following photoexcitation, we observe Coulomb explosion signatures of highly bent and stretched excited-state geometries involved in the photodissociation. Aided by a model to interpret such changes, we build a comprehensive picture of the photoinduced nuclear dynamics that follows initial bending and stretching motions, as the reaction proceeds towards photodissociation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1979

CS2 - Candidate for the 3150-A Venus band

The 3150-A absorption on Venus, found by Barker et al. (1975), may be due to carbon disulfide. The stability and thermodynamics of the carbon chalcogenides are briefly discussed.

Young, A. T.↗