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BN is SC16 CuCl, stable at 5GPa-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. B3+ is bonded to four equivalent N3- atoms to form a mixture of edge and corner-sharing BN4 tetrahedra. There are a spread of B–N bond distances ranging from 1.51–1.65 Å. N3- is bonded to four equivalent B3+ atoms to form a mixture of distorted edge and corner-sharing NB4 trigonal pyramids.
(CuCl)LaNb2O7 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form a mixture of corner and face-sharing LaO12 cuboctahedra. There are eight shorter (2.69 Å) and four longer (2.77 Å) La–O bond lengths. Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.80–2.29 Å. Cu2+ is bonded in a distorted linear geometry to two equivalent O2- and four equivalent Cl1- atoms. Both Cu–O bond lengths are 1.83 Å. All Cu–Cl bond lengths are 2.77 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a linear geometry to one Nb5+ and one Cu2+ atom. In the third O2- site, O2- is bonded to four equivalent La3+ and two equivalent Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLa4Nb2 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded in a square co-planar geometry to four equivalent Cu2+ atoms.
Sb2SnZn is SC16 CuCl, stable at 5GPa-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form ZnSb4 trigonal pyramids that share corners with three equivalent SnSb4 trigonal pyramids and corners with nine ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.63–2.79 Å. In the second Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form corner-sharing ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.65–2.77 Å. In the third Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form distorted corner-sharing ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.62–2.77 Å. In the fourth Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form distorted corner-sharing ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.62–2.86 Å. In the fifth Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form distorted corner-sharing ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.62–2.88 Å. In the sixth Zn2+ site, Zn2+ is bonded to four Sb3- atoms to form distorted ZnSb4 trigonal pyramids that share corners with three equivalent SnSb4 tetrahedra and corners with nine ZnSb4 trigonal pyramids. There are a spread of Zn–Sb bond distances ranging from 2.63–2.97 Å. There are six inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form SnSb4 tetrahedra that share corners with six equivalent SnSb4 tetrahedra, corners with three equivalent ZnSb4 trigonal pyramids, and corners with three equivalent SnSb4 trigonal pyramids. There are a spread of Sn–Sb bond distances ranging from 2.91–2.98 Å. In the second Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form distorted corner-sharing SnSb4 trigonal pyramids. There are a spread of Sn–Sb bond distances ranging from 2.93–3.06 Å. In the third Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form corner-sharing SnSb4 tetrahedra. There are a spread of Sn–Sb bond distances ranging from 2.90–2.96 Å. In the fourth Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form distorted corner-sharing SnSb4 trigonal pyramids. There are a spread of Sn–Sb bond distances ranging from 2.93–2.97 Å. In the fifth Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form distorted SnSb4 trigonal pyramids that share corners with three equivalent ZnSb4 trigonal pyramids and corners with nine SnSb4 trigonal pyramids. There are a spread of Sn–Sb bond distances ranging from 2.92–3.01 Å. In the sixth Sn4+ site, Sn4+ is bonded to four Sb3- atoms to form distorted corner-sharing SnSb4 trigonal pyramids. There are a spread of Sn–Sb bond distances ranging from 2.92–2.97 Å. There are twelve inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded to four Zn2+ atoms to form SbZn4 trigonal pyramids that share corners with three equivalent SbZnSn3 tetrahedra and corners with nine SbZn4 trigonal pyramids. In the second Sb3- site, Sb3- is bonded to four Zn2+ atoms to form corner-sharing SbZn4 trigonal pyramids. In the third Sb3- site, Sb3- is bonded to four Zn2+ atoms to form distorted corner-sharing SbZn4 trigonal pyramids. In the fourth Sb3- site, Sb3- is bonded to four Zn2+ atoms to form distorted corner-sharing SbZn4 trigonal pyramids. In the fifth Sb3- site, Sb3- is bonded to four Zn2+ atoms to form distorted corner-sharing SbZn4 trigonal pyramids. In the sixth Sb3- site, Sb3- is bonded to three equivalent Zn2+ and one Sn4+ atom to form distorted corner-sharing SbZn3Sn trigonal pyramids. In the seventh Sb3- site, Sb3- is bonded to four Sn4+ atoms to form distorted SbSn4 trigonal pyramids that share corners with three equivalent SbSn4 tetrahedra and corners with nine SbZn3Sn trigonal pyramids. In the eighth Sb3- site, Sb3- is bonded to four Sn4+ atoms to form distorted corner-sharing SbSn4 tetrahedra. In the ninth Sb3- site, Sb3- is bonded to four Sn4+ atoms to form distorted corner-sharing SbSn4 trigonal pyramids. In the tenth Sb3- site, Sb3- is bonded to four Sn4+ atoms to form distorted corner-sharing SbSn4 trigonal pyramids. In the eleventh Sb3- site, Sb3- is bonded to four Sn4+ atoms to form SbSn4 trigonal pyramids that share corners with three equivalent SbZnSn3 tetrahedra and corners with nine SbSn4 trigonal pyramids. In the twelfth Sb3- site, Sb3- is bonded to one Zn2+ and three equivalent Sn4+ atoms to form distorted SbZnSn3 tetrahedra that share corners with six equivalent SbZnSn3 tetrahedra and corners with six SbZn4 trigonal pyramids.
AsZn is SC16 CuCl, stable at 5GPa structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Zn2+ is bonded to four equivalent As2- atoms to form a mixture of edge and corner-sharing ZnAs4 tetrahedra. There are a spread of Zn–As bond distances ranging from 2.50–2.72 Å. As2- is bonded in a 5-coordinate geometry to four equivalent Zn2+ and one As2- atom. The As–As bond length is 2.46 Å.
ZnSb is SC16 CuCl, stable at 5GPa structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Zn2+ is bonded to four equivalent Sb2- atoms to form a mixture of distorted corner and edge-sharing ZnSb4 tetrahedra. There are a spread of Zn–Sb bond distances ranging from 2.69–2.91 Å. Sb2- is bonded in a 5-coordinate geometry to four equivalent Zn2+ and one Sb2- atom. The Sb–Sb bond length is 2.84 Å.
GaP is SC16 CuCl, stable at 5GPa structured and crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. Ga3+ is bonded to four equivalent P3- atoms to form corner-sharing GaP4 tetrahedra. There are one shorter (2.34 Å) and three longer (2.43 Å) Ga–P bond lengths. P3- is bonded to four equivalent Ga3+ atoms to form corner-sharing PGa4 trigonal pyramids.
ZnBi is SC16 CuCl, stable at 5GPa structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Zn is bonded in a 5-coordinate geometry to one Zn and four equivalent Bi atoms. The Zn–Zn bond length is 2.77 Å. There are a spread of Zn–Bi bond distances ranging from 2.80–3.03 Å. Bi is bonded in a 5-coordinate geometry to four equivalent Zn and one Bi atom. The Bi–Bi bond length is 3.05 Å.
AlAs is SC16 CuCl, stable at 5GPa structured and crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. Al3+ is bonded to four equivalent As3- atoms to form corner-sharing AlAs4 tetrahedra. There are one shorter (2.44 Å) and three longer (2.53 Å) Al–As bond lengths. As3- is bonded to four equivalent Al3+ atoms to form corner-sharing AsAl4 trigonal pyramids.
(CuCl)LaNb2O7 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. There are a spread of La–O bond distances ranging from 2.67–2.80 Å. Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.82–2.25 Å. Cu2+ is bonded in a distorted see-saw-like geometry to two equivalent O2- and two equivalent Cl1- atoms. Both Cu–O bond lengths are 1.86 Å. Both Cu–Cl bond lengths are 2.34 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent La3+ and two equivalent Nb5+ atoms. In the third O2- site, O2- is bonded to four equivalent La3+ and two equivalent Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLa4Nb2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded in a linear geometry to one Nb5+ and one Cu2+ atom. Cl1- is bonded in a bent 120 degrees geometry to two equivalent Cu2+ atoms.
SnSb is SC16 CuCl, stable at 5GPa-like structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Sn2+ is bonded to four equivalent Sb2- atoms to form corner-sharing SnSb4 trigonal pyramids. There are one shorter (2.90 Å) and three longer (2.98 Å) Sn–Sb bond lengths. Sb2- is bonded to four equivalent Sn2+ atoms to form corner-sharing SbSn4 trigonal pyramids.
Development, fabrication and applications of CdS solar cells are reviewed in detail. The suitability of CdS cells for large solar panels and microcircuitry, and their low cost, are emphasized. Developments are reviewed by manufacturer-developer. Vapor phase deposition of thin-film solar cells, doping and co-evaporation, sputtering, chemical spray, and sintered layers are reviewed, in addition to spray deposition, monograin layer structures, and silk screening. Formation of junctions by electroplating, evaporation, brushing, CuCl dip, and chemiplating are discussed, along with counterelectrode fabrication, VPD film structures, the Cu2S barrier layer, and various photovoltaic effects (contact photovoltage, light intensity variation, optical enhancement), and various other CdS topics.
Addition of small amounts of hydrogen chloride to the buffer gas of a double-pulse CuCl laser causes an increase in the production of copper atoms in the ground state. A maximum laser energy increase of 15% was observed and the span of delay times for which laser action occurred increased.
The laser energy at optimum time delay of a double-pulsed CuCl laser was experimentally determined to be a logarithmic function of the initial current rise of the pumping pulse over the total circuit inductance range 1 to 12 microhenrys. The minimum delay was found to decrease with initial current rise, which implies that faster rising current pulses are more efficient at pumping copper atoms from the ground state to the upper laser level because lasing threshold occurs with a higher population in the lower laser level.
By use of low-inductance (0.5micro H) discharge circuits, pulses of 9.6 mJ were obtained from a double-pulsed CuCl laser. An oscillator-amplifier configuration produced a pulse energy of 11 mJ. Scaling studies indicate that additional increases in the laser energy could be obtained by increasing the discharge voltage above 20 kV and/or by increasing the laser-tube dimensions.
Diamond cells were constructed for use to 1 Mbar. A refrigerator for cooling diamond cells was adapted for studies between 15 and 300 K. A cryostat for superconductivity studies between 1.5 to 300 K was constructed. Optical equipment was constructed for fluorescence, transmission, and reflectance studies. X-ray equipment was adapted for use with diamond cells. Experimental techniques were developed for X-ray diffraction studies using synchrotron radiation. AC susceptibility techniques were developed for detecting superconducting transitions. The following materials were studied: compressed solidified gases (Xe, Ar), semiconductors (Ge, Si, GaAs), superconductors (Nb3Ge, Nb3Si, Nb3As, CuCl), molecular crystals (I).
Optical bistability and its potential for optical signal processing and communications are reviewed. Recent experimental results in semiconductor optical bistability are presented. In particular, optical bistability in GaAs-AlGaAs superlattices and CuCl, ZnS, and ZnSe is discussed.
The reaction of the surfaces of the new high-temperature superconductor YBa2Cu3O(7-x) with nonaqueous halogen solutions is investigated, and the species formed in the reactions are identified. Treatment of films with HF/EtOH (EtOH = HI in absolute ethanol) results in the formation of an oxyfluoride with Y:Ba:Cu relative concentrations of 1:4:3. Results of X-ray photoelectron spectroscopy of HF-treated films are consistent with the formation of CuF, a compound which does not exist in bulk form. Treatment of films with HCl/EtOH results primarily in the formation of BaCl2, with smaller amounts of YCl3, CuCl, and CuCl2. Treatment with Br2/EtOH or HBr/EtOH results in the formation of YBr3, BaBr2, and CuBr with relative concentrations of 1:4:3.
The high vapor pressure of volatile metal halides and chalcogenides (e.g., of Cu, Zn, Sn, Pb, As, Sb, Bi) at typical Venus surface temperatures, coupled with the altitude-dependent temperature gradient of approximately 8.5 K/km, is calculated to transport volatile metal vapors to the highlands of Venus, where condensation and accumulation will occur. The predicted geochemistry of volatile metals on Venus is supported by observations of CuCl in volcanic gases at Kilauea and Nyiragongo, and large enrichments of these and other volatile elements in terrestrial volcanic aerosols. A one-dimensional finite difference vapor transport model shows the diffusive migration of a thickness of 0.01 to greater than 10 microns/yr of moderately to highly volatile phases (e.g., metal halides and chalcogenides) from the hot lowlands (740 K) to the cold highlands (660 K) on Venus. The diffusive transport of volatile phases on Venus may explain the observed low emissivity of the Venusian highlands, hazes at 6-km altitude observed by two Pioneer Venus entry probes, and the Pioneer Venus entry probe anomalies at 12.5 km.