SEARCH · Search NASA

Results for “SCl”

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.

SourceResearch connectionFrom yearThrough year

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

At least 19 records

All sources NASA NTRS DOE OSTI

NASA NTRS1994

SCL: An off-the-shelf system for spacecraft control

In this age of shrinking military, civil, and commercial space budgets, an off-the-shelf solution is needed to provide a multimission approach to spacecraft control. A standard operational interface which can be applied to multiple spacecraft allows a common approach to ground and space operations. A trend for many space programs has been to reduce operational staff by applying autonomy to the spacecraft and to the ground stations. The Spacecraft Command Language (SCL) system developed by Interface and Control Systems, Inc. (ICS) provides an off-the-shelf solution for spacecraft operations. The SCL system is designed to provide a hyper-scripting interface which remains standard from program to program. The spacecraft and ground station hardware specifics are isolated to provide the maximum amount of portability from system to system. Uplink and downlink interfaces are also isolated to allow the system to perform independent of the communications protocols chosen. The SCL system can be used for both the ground stations and the spacecraft, or as a value added package for existing ground station environments. The SCL system provides an expanded stored commanding capability as well as a rule-based expert system on-board. The expert system allows reactive control on-board the spacecraft for functions such as electrical power systems (EPS), thermal control, etc. which have traditionally been performed on the ground. The SCL rule and scripting capability share a common syntax allowing control of scripts from rules and rules from scripts. Rather than telemeter over sampled data to the ground, the SCL system maintains a database on-board which is available for interrogation by the scripts and rules. The SCL knowledge base is constructed on the ground and uploaded to the spacecraft. The SCL system follows an open-systems approach allowing other tasks to communicate with SCL on the ground and in space. The SCL system was used on the Clementine program (launched January 25, 1994) and is required to have bidirectional communications with the guidance, navigation, and control (GNC) algorithms which were written as another task. Sequencing of the spacecraft maneuvers are handled by SCL, but the low-level thruster pulse commands are handled by the GNC software. Attitude information is reported back as telemetry, allowing the SCL expert system to inference on the changing data. The Clementine SCL flight software was largely reused from another Naval Center for Space Technology (NCST) satellite program. This paper details the SCL architecture and how an off-the-shelf solution makes sense for multimission spacecraft programs. The Clementine mission will be used as a case study in the application of the SCL to a 'fast track' program. The benefits of such a system in a 'better, cheaper, faster' climate will be discussed.

Buckley, Brian↗

DOE OSTI2026

Optics reconstruction in the SCL section of the FNAL Linac

The Side-Coupled Linac (SCL) section of the FNAL linac accelerates the beam from 116 MeV to 401.5 MeV, operating at 22-24 mA beam current. Transverse focusing is performed by 32 quadrupoles, and the beam orbit is guided by 19 dipole correctors and measured by 29 BPMs. The bunch length is measured in a single location by a Bunch Shape Monitor (BSM). This paper presents a three-step reconstruction of the machine optics. First, the transverse and longitudinal Twiss parameters at the start of the SCL section are determined using quadrupole scans and BSM measurements at different settings of an upstream cavity. Second, the quadrupole calibrations are adjusted based on differential-trajectory measurements. Finally, the beam is propagated along the SCL linac using the code TraceWin. A comparison between TraceWin simulations and the beam envelope measured by the 12 wire scanners of the SCL linac was performed. Transverse and longitudinal beam parameters at the entrance and exit of the SCL section will be reported.

Carneiro, Jean-Paul [Fermilab]↗

DOE OSTI2025

Optics Reconstruction in the SCL Section of the FNAL Linac

The Side-CoupledLinac (SCL) section oftheFNAL linac acceleratesthe beamfrom 117 MeV to 401.5 MeV, operatingat 22-24mA beam current. Transverse focusing is performedby32 quadrupoles, and the beam orbit is guidedby19dipolecorrectors andmeasuredby29 BPMs. The bunch length is measured in a single location by a Bunch Shape Monitor (BSM). This paper presents a three-step reconstruction of the machine optics. First, the transverse and longitudinal Twiss parameters at the start of the SCL section are determined using quadrupole scans and BSM measurements at different settings o fan upstream cavity. Second, the quadrupole calibrations are adjusted based on differential-trajectory measurements. Finally, the beam is propagated along the SCL linac using the code Trace Win. A comparison between Trace Win simulations and the beam envelope measured bythe12wirescanners of the SCL linac was performed. Transverse and longitudinal beam parameters at the entrance of the transition section will be reported

Carneiro, Jean-Paul [Fermilab]↗

DOE OSTI2020

Materials Data on TaP4(SCl)5 by Materials Project

TaP4(SCl)5 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two TaP4(SCl)5 clusters. Ta3+ is bonded in a distorted octahedral geometry to one S2- and five Cl1- atoms. The Ta–S bond length is 2.73 Å. There are a spread of Ta–Cl bond distances ranging from 2.29–2.37 Å. There are four inequivalent P3+ sites. In the first P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of P–S bond distances ranging from 1.99–2.11 Å. In the second P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of P–S bond distances ranging from 2.13–2.16 Å. In the third P3+ site, P3+ is bonded in a single-bond geometry to one S2- atom. The P–S bond length is 2.06 Å. In the fourth P3+ site, P3+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.13 Å) and one longer (2.17 Å) P–S bond lengths. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two P3+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two P3+ atoms. In the third S2- site, S2- is bonded in a 2-coordinate geometry to one Ta3+ and one P3+ atom. In the fourth S2- site, S2- is bonded in a distorted L-shaped geometry to two P3+ atoms. In the fifth S2- site, S2- is bonded in a water-like geometry to two P3+ atoms. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Re3(SCl)7 by Materials Project

Re3(SCl)7 crystallizes in the trigonal P31c space group. The structure is two-dimensional and consists of two Re3(SCl)7 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to five S2- and two Cl1- atoms to form distorted face-sharing ReS5Cl2 pentagonal bipyramids. There are a spread of Re–S bond distances ranging from 2.36–2.47 Å. Both Re–Cl bond lengths are 2.39 Å. In the second Re7+ site, Re7+ is bonded to five S2- and two Cl1- atoms to form distorted face-sharing ReS5Cl2 pentagonal bipyramids. There are a spread of Re–S bond distances ranging from 2.37–2.46 Å. There are one shorter (2.37 Å) and one longer (2.43 Å) Re–Cl bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Re7+ and one S2- atom. The S–S bond length is 2.07 Å. In the second S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent Re7+ atoms. In the third S2- site, S2- is bonded in a 7-coordinate geometry to two equivalent Re7+ and one Cl1- atom. The S–Cl bond length is 2.71 Å. In the fourth S2- site, S2- is bonded in a 7-coordinate geometry to two equivalent Re7+, one S2-, and four Cl1- atoms. There are a spread of S–Cl bond distances ranging from 2.71–3.60 Å. In the fifth S2- site, S2- is bonded in a 9-coordinate geometry to three equivalent Re7+ atoms. In the sixth S2- site, S2- is bonded in a 6-coordinate geometry to three equivalent Re7+ atoms. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Re7+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ and two equivalent S2- atoms. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Re7+ and one S2- atom. In the fifth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to three equivalent S2- atoms. In the sixth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to three equivalent S2- atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on H18RuC6(SCl)3 by Materials Project

RuC6H18(SCl)3 is beta-like structured and crystallizes in the orthorhombic Pna2_1 space group. The structure is zero-dimensional and consists of four RuC6H18(SCl)3 clusters. Ru5+ is bonded in an octahedral geometry to three S2- and three Cl1- atoms. There are a spread of Ru–S bond distances ranging from 2.39–2.41 Å. There are a spread of Ru–Cl bond distances ranging from 2.36–2.39 Å. There are six inequivalent C+2.33- sites. In the first C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.81 Å. In the second C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.81 Å. In the third C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.81 Å. In the fourth C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.80 Å. In the fifth C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.80 Å. In the sixth C+2.33- site, C+2.33- is bonded in a trigonal non-coplanar geometry to three H1+ and one S2- atom. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. The C–S bond length is 1.81 Å. There are eighteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the seventeenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. In the eighteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+2.33- atom. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a trigonal non-coplanar geometry to one Ru5+ and two C+2.33- atoms. In the second S2- site, S2- is bonded in a trigonal non-coplanar geometry to one Ru5+ and two C+2.33- atoms. In the third S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to one Ru5+ and two C+2.33- atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ru5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ru5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ru5+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on SnSb2H24C8(SCl)2 by Materials Project

SnC8Sb2H24(SCl)2 is Protactinium structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two SnC8Sb2H24(SCl)2 clusters. Sn4+ is bonded to two equivalent C2-, two equivalent S2-, and two equivalent Cl1- atoms to form SnC2S2Cl2 octahedra that share corners with two equivalent SbC3S tetrahedra. Both Sn–C bond lengths are 2.16 Å. Both Sn–S bond lengths are 2.79 Å. Both Sn–Cl bond lengths are 2.64 Å. There are four inequivalent C2- sites. In the first C2- site, C2- is bonded in a distorted trigonal non-coplanar geometry to one Sb3- and three H1+ atoms. The C–Sb bond length is 2.15 Å. There is two shorter (1.09 Å) and one longer (1.10 Å) C–H bond length. In the second C2- site, C2- is bonded in a distorted trigonal non-coplanar geometry to one Sb3- and three H1+ atoms. The C–Sb bond length is 2.14 Å. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. In the third C2- site, C2- is bonded in a distorted trigonal non-coplanar geometry to one Sb3- and three H1+ atoms. The C–Sb bond length is 2.14 Å. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. In the fourth C2- site, C2- is bonded in a distorted trigonal non-coplanar geometry to one Sn4+ and three H1+ atoms. There is two shorter (1.09 Å) and one longer (1.10 Å) C–H bond length. Sb3- is bonded to three C2- and one S2- atom to form SbC3S tetrahedra that share a cornercorner with one SnC2S2Cl2 octahedra. The corner-sharing octahedral tilt angles are 73°. The Sb–S bond length is 2.33 Å. There are twelve inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one C2- atom. S2- is bonded in a water-like geometry to one Sn4+ and one Sb3- atom. Cl1- is bonded in a single-bond geometry to one Sn4+ atom.

36 MATERIALS SCIENCE↗

NASA NTRS2014

X-Ray Observations of VY Scl-Type Nova-Like Binaries in the High and Low State

Four VY Scl-type nova-like systems were observed in X-rays during both the low- and the high-optical states. We examined Chandra, ROSAT, Swift and Suzaku archival observations of BZ Cam, MV Lyr, TT Ari and V794 Aql. The X-ray flux of BZ Cam is higher during the low state, but there is no supersoft X-ray source (SSS) as hypothesized in previous articles. No SSS was detected in the low state of the any of the other systems, with the X-ray flux decreasing by a factor between 2 and 50. The best fit to the Swift X-ray spectra is obtained with a multicomponent model of plasma in collisional ionization equilibrium. The high-state high-resolution spectra of TT Ari taken with Chandra Advanced CCD Imaging Spectrometer (ACIS-S) and the Chandra High Energy Transmission Grating (HETG) shows a rich emission line spectrum, with prominent lines of Mg, Si, Ne and S. The complexity of this spectrum seems to have origin in more than one region, or more than one single physical mechanism. While several emission lines are consistent with a cooling flow in an accretion stream, there is at least an additional component. We discuss the origin of this component, which is probably arising in a wind from the system. We also examine the possibility that the VY Scl systems may be intermediate polars, and that while the boundary layer of the accretion disc emits only in the extreme ultraviolet, part of the X-ray flux may be due to magnetically driven accretion.

accretion↗

DOE OSTI2017

Materials Data on SCl by Materials Project

SCl crystallizes in the orthorhombic Fdd2 space group. The structure is zero-dimensional and consists of sixteen disulfur dichloride molecules. there are two inequivalent S sites. In the first S site, S is bonded in a distorted water-like geometry to one S and one Cl atom. The S–S bond length is 1.93 Å. The S–Cl bond length is 2.11 Å. In the second S site, S is bonded in a distorted water-like geometry to one S and one Cl atom. The S–Cl bond length is 2.11 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one S atom. In the second Cl site, Cl is bonded in a single-bond geometry to one S atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ca2Cu(SCl)2 by Materials Project

Ca2Cu(SCl)2 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca2+ is bonded to four S2- and two equivalent Cl1- atoms to form CaS4Cl2 octahedra that share corners with six equivalent CaS4Cl2 octahedra, edges with four equivalent CaS4Cl2 octahedra, and edges with four equivalent CuS2Cl4 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ca–S bond lengths are 2.80 Å. Both Ca–Cl bond lengths are 2.65 Å. Cu2+ is bonded to two equivalent S2- and four equivalent Cl1- atoms to form CuS2Cl4 octahedra that share corners with six equivalent CuS2Cl4 octahedra and edges with eight equivalent CaS4Cl2 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Cu–S bond lengths are 2.65 Å. All Cu–Cl bond lengths are 2.80 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a square co-planar geometry to four equivalent Ca2+ atoms. In the second S2- site, S2- is bonded to four equivalent Ca2+ and two equivalent Cu2+ atoms to form corner-sharing SCa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded in a square co-planar geometry to two equivalent Ca2+ and two equivalent Cu2+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ba2Cu(SCl)2 by Materials Project

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Sr2Cu(SCl)2 by Materials Project

Sr2Cu(SCl)2 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to four equivalent S2- and five equivalent Cl1- atoms. All Sr–S bond lengths are 3.06 Å. There are one shorter (2.97 Å) and four longer (3.42 Å) Sr–Cl bond lengths. Cu2+ is bonded to four equivalent S2- and two equivalent Cl1- atoms to form corner-sharing CuS4Cl2 octahedra. The corner-sharing octahedral tilt angles are 0°. All Cu–S bond lengths are 2.30 Å. Both Cu–Cl bond lengths are 3.05 Å. S2- is bonded to four equivalent Sr2+ and two equivalent Cu2+ atoms to form a mixture of corner, edge, and face-sharing SSr4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded in a 6-coordinate geometry to five equivalent Sr2+ and one Cu2+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ba2Cu(SCl)2 by Materials Project

Ba2Cu(SCl)2 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to five equivalent S2- and four equivalent Cl1- atoms. There are one shorter (3.06 Å) and four longer (3.44 Å) Ba–S bond lengths. All Ba–Cl bond lengths are 3.31 Å. Cu2+ is bonded to two equivalent S2- and four equivalent Cl1- atoms to form corner-sharing CuS2Cl4 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Cu–S bond lengths are 2.41 Å. All Cu–Cl bond lengths are 2.43 Å. S2- is bonded to five equivalent Ba2+ and one Cu2+ atom to form distorted SBa5Cu octahedra that share corners with five equivalent SBa5Cu octahedra, corners with twelve equivalent ClBa4Cu2 octahedra, edges with eight equivalent SBa5Cu octahedra, and faces with four equivalent ClBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–57°. Cl1- is bonded to four equivalent Ba2+ and two equivalent Cu2+ atoms to form distorted ClBa4Cu2 octahedra that share corners with two equivalent ClBa4Cu2 octahedra, corners with twelve equivalent SBa5Cu octahedra, edges with two equivalent ClBa4Cu2 octahedra, faces with four equivalent SBa5Cu octahedra, and faces with four equivalent ClBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–57°.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Cs3Re6(SCl)7 by Materials Project

Cs3Re6(SCl)7 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to two S2- and five Cl1- atoms. There are one shorter (3.59 Å) and one longer (3.79 Å) Cs–S bond lengths. There are a spread of Cs–Cl bond distances ranging from 3.60–3.97 Å. In the second Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to one S2- and six Cl1- atoms. The Cs–S bond length is 3.78 Å. There are a spread of Cs–Cl bond distances ranging from 3.56–3.96 Å. In the third Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to five S2- and five Cl1- atoms. There are a spread of Cs–S bond distances ranging from 3.69–4.16 Å. There are a spread of Cs–Cl bond distances ranging from 3.61–4.10 Å. There are six inequivalent Re3+ sites. In the first Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are a spread of Re–S bond distances ranging from 2.41–2.43 Å. The Re–Cl bond length is 2.46 Å. In the second Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.38 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.45 Å) and one longer (2.53 Å) Re–Cl bond lengths. In the third Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are a spread of Re–S bond distances ranging from 2.41–2.43 Å. The Re–Cl bond length is 2.43 Å. In the fourth Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.38 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.41 Å) and one longer (2.55 Å) Re–Cl bond lengths. In the fifth Re3+ site, Re3+ is bonded to four S2- and one Cl1- atom to form edge-sharing ReS4Cl square pyramids. There are two shorter (2.42 Å) and two longer (2.43 Å) Re–S bond lengths. The Re–Cl bond length is 2.44 Å. In the sixth Re3+ site, Re3+ is bonded to three S2- and two Cl1- atoms to form edge-sharing ReS3Cl2 square pyramids. There are one shorter (2.37 Å) and two longer (2.42 Å) Re–S bond lengths. There are one shorter (2.41 Å) and one longer (2.56 Å) Re–Cl bond lengths. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Re3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three Re3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to two Cs1+ and three Re3+ atoms. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to two Cs1+ and three Re3+ atoms. In the seventh S2- site, S2- is bonded in a 4-coordinate geometry to two Cs1+ and three Re3+ atoms. There are seven inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to three Cs1+ and one Re3+ atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to three Cs1+ and one Re3+ atom. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the fourth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the fifth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the sixth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Cs1+ and one Re3+ atom. In the seventh Cl1- site, Cl1- is bonded in a 4-coordinate geometry to two Cs1+ and three Re3+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on CuPb2(SCl)2 by Materials Project

CuPb2(SCl)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Cu2+ is bonded to two equivalent S2- and four equivalent Cl1- atoms to form corner-sharing CuS2Cl4 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Cu–S bond lengths are 2.73 Å. All Cu–Cl bond lengths are 2.25 Å. Pb2+ is bonded in a 9-coordinate geometry to five equivalent S2- and four equivalent Cl1- atoms. There are one shorter (2.72 Å) and four longer (3.18 Å) Pb–S bond lengths. All Pb–Cl bond lengths are 3.47 Å. S2- is bonded to one Cu2+ and five equivalent Pb2+ atoms to form a mixture of distorted edge and corner-sharing SCuPb5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Cl1- is bonded in a linear geometry to two equivalent Cu2+ and four equivalent Pb2+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

MACHO 311.37557.169: A VY Scl star

Abstract Optical surveys, such as the MACHO project, often uncover variable stars whose classification requires follow‐up observations by other instruments. We performed X‐ray spectroscopy and photometry of the unusual variable star MACHO 311.37557.169 with XMM‐Newton in April 2018, supplemented by archival X‐ray and optical spectrographic data. The star has a bolometric X‐ray luminosity of about 1 × 10 32 erg s −1 cm −2 and a heavily absorbed two‐temperature plasma spectrum. The shape of its light curve, its overall brightness, its X‐ray spectrum, and the emission lines in its optical spectrum suggest that it is most likely a VY Scl cataclysmic variable.

Wörpel, Hauke↗

NASA NTRS2001

X-Ray Spectra of VY Scl Stars Are Not Blackbodies

Using ASCA data, we find, contrary to other researchers using ROSAT data, that the X, ray spectra of the VY Scl stars TT Ari and KR Aur are poorly fit by an absorbed blackbody model but are well fit by an absorbed thermal plasma model. The different conclusions about the nature of the X-ray spectrum of KR Aur may be due to differences in the accretion rate, since this star was in a high optical state during the ROSAT observation, but in an intermediate optical state during the ASCA observation. TT Ari, on the other hand, was in a high optical state during both observations, so directly contradicts the hypothesis that the X-ray spectra of VY Sol stars in their high optical states are blackbodies. Instead, based on theoretical expectations and the ASCA, Chandra, and XMM spectra of other nonmagnetic cataclysmic variables, we believe that the X-ray spectra of VY Sol stars in their low and high optical states are due to hot thermal plasma in the boundary layer between the accretion disk and the surface of the white dwarf, and appeal to the acquisition of Chandra and XMM grating spectra to test this prediction.

Mauche, C. W.↗

DOE OSTI2020

Materials Data on Hg3(SCl)2 by Materials Project

Hg3S2Cl2 crystallizes in the cubic I2_13 space group. The structure is three-dimensional. Hg2+ is bonded in a distorted see-saw-like geometry to two equivalent S2- and two equivalent Cl1- atoms. Both Hg–S bond lengths are 2.45 Å. Both Hg–Cl bond lengths are 2.95 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Hg2+ atoms. Cl1- is bonded in a distorted trigonal planar geometry to three equivalent Hg2+ atoms.

36 MATERIALS SCIENCE↗