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NS crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one 1,3,2,4-dithiadiazetidine molecule. N1+ is bonded in an L-shaped geometry to two equivalent S1- atoms. There is one shorter (1.65 Å) and one longer (1.66 Å) N–S bond length. S1- is bonded in an L-shaped geometry to two equivalent N1+ atoms.
Ni(NS)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight Ni(NS)4 clusters. Ni4+ is bonded in a 2-coordinate geometry to two S2- atoms. There are one shorter (2.11 Å) and one longer (2.12 Å) Ni–S bond lengths. There are four inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a distorted single-bond geometry to one S2- atom. The N–S bond length is 1.54 Å. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.62 Å) and one longer (1.63 Å) N–S bond length. In the third N1+ site, N1+ is bonded in a distorted single-bond geometry to one S2- atom. The N–S bond length is 1.54 Å. In the fourth N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S2- atoms. Both N–S bond lengths are 1.62 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to one Ni4+ and one N1+ atom. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two N1+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to one Ni4+ and one N1+ atom. In the fourth S2- site, S2- is bonded in a water-like geometry to two N1+ atoms.
CNH2S2NH4 crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of eight ammonium molecules and eight dithiocarbamic acid molecules.
NS crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four NS clusters. N1+ is bonded in a distorted single-bond geometry to one S1- atom. The N–S bond length is 1.49 Å. S1- is bonded in a distorted single-bond geometry to one N1+ atom.
Pd(NS)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four Pd(NS)4 clusters. Pd4+ is bonded in an L-shaped geometry to two S2- atoms. There are one shorter (2.24 Å) and one longer (2.25 Å) Pd–S bond lengths. There are four inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S2- atoms. Both N–S bond lengths are 1.62 Å. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.62 Å) and one longer (1.63 Å) N–S bond length. In the third N1+ site, N1+ is bonded in a single-bond geometry to one S2- atom. The N–S bond length is 1.54 Å. In the fourth N1+ site, N1+ is bonded in a single-bond geometry to one S2- atom. The N–S bond length is 1.54 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to one Pd4+ and one N1+ atom. In the second S2- site, S2- is bonded in a water-like geometry to one Pd4+ and one N1+ atom. In the third S2- site, S2- is bonded in a bent 120 degrees geometry to two N1+ atoms. In the fourth S2- site, S2- is bonded in a bent 120 degrees geometry to two N1+ atoms.
NS is lead oxide structured and crystallizes in the tetragonal P4/nmm space group. The structure is two-dimensional and consists of one NS sheet oriented in the (0, 0, 1) direction. N1+ is bonded to four equivalent S1- atoms to form a mixture of distorted corner and edge-sharing NS4 trigonal pyramids. All N–S bond lengths are 1.93 Å. S1- is bonded in a distorted see-saw-like geometry to four equivalent N1+ atoms.
Pb(NS)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two Pb(NS)2 clusters. Pb2+ is bonded in a 1-coordinate geometry to one N1+ and two equivalent S2- atoms. The Pb–N bond length is 2.27 Å. There are one shorter (2.78 Å) and one longer (2.93 Å) Pb–S bond lengths. There are two inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.59 Å) and one longer (1.71 Å) N–S bond length. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to one Pb2+ and one S2- atom. The N–S bond length is 1.52 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to two equivalent Pb2+ and one N1+ atom. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two N1+ atoms.
CNH2S2NH4 crystallizes in the orthorhombic Pca2_1 space group. The structure is zero-dimensional and consists of four ammonium molecules and four dithiocarbamic acid molecules.
In the present study, the local atomic structure of a Nb3Sn superconductor sample has been probed by X-ray absorption fine structure (XAFS) as a function of hydrostatic pressure (from ambient up to 26 GPa) using a diamond anvil cell set-up. The analysis of the Nb-K edge extended X-ray absorption fine structure (EXAFS) data was carried out combining standard multi shell structural refinement and reverse Monte Carlo method to provide detailed in situ characterization of the pressure-induced evolution of the Nb local structure in Nb3Sn. The results highlight a complex evolution of Nb chains at the local atomic scale, with a peculiar correlated displacement of Nb–Nb and Nb–Nb–Nb configurations. Such a local effect appears related to anomalies evidenced by X-ray diffraction in other superconductors belonging to the same A15 crystallographic structure.
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Recent advances in copper chalcogenide-based nanocrystals (NCs), copper sulfide, and copper selenide derived nanostructures, have drawn considerable attention. However, reports of crystal phase and shape engineering of binary or ternary copper telluride NCs remain rare. Here, a colloidal hot-injection approach for producing binary copper/tin telluride, and ternary copper tin telluride NCs with controllable compositions, crystal structures, and morphologies is reported. Here, the crystal phase and growth behavior of these tellurides are systematically studied from both experimental and theoretical perspectives.
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New high-field accelerator magnets based on $Nb_3Sn$ superconductors are pushing the boundaries of magnet design and quench protection towards new limits. While their large stored energies and current densities result in a very challenging scenario for magnet protection, their great electromagnetic forces create also new requirements in terms of magnet design and stress management techniques. Furthermore, the strain sensitivity of $Nb_3Sn$ cables turns the electro-mechanical limits of the conductor into a parameter of the highest importance, where conductor degradation becomes a critical aspect in magnet operation. The coupling of all the above-mentioned considerations during quench is a case of special interest that adds further complexity to the design of $Nb_3Sn$ magnets. The objective of this paper is to provide a complete two-dimensional investigation of the coil and magnet structure mechanics during a quench event. Here, the analysis is performed using a combination of finite element codes that provide the necessary input for the mechanical study. The core of the modelling strategy relies on a thermal-electric model, whose results are directly used as loads in the mechanical simulation. In doing so, the stress evolution during and after a quench is obtained. We focus for this time in the analysis of a quench heater protected magnet, where dynamic effects are of less importance in contrast to other protection systems like CLIQ.