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NaAuC2 crystallizes in the tetragonal P4/mmm space group. The structure is one-dimensional and consists of one sodium molecule and one AuC2 ribbon oriented in the (0, 0, 1) direction. In the AuC2 ribbon, Au1- is bonded in a linear geometry to two equivalent C atoms. Both Au–C bond lengths are 2.00 Å. C is bonded in a distorted linear geometry to one Au1- and one C atom. The C–C bond length is 1.25 Å.
YH3 is Sodium arsenide structured and crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Y3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Y–H bond distances ranging from 2.12–2.37 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Y3+ atoms. In the second H1- site, H1- is bonded to four equivalent Y3+ atoms to form a mixture of edge, corner, and face-sharing HY4 tetrahedra.
Investigations of solvothermal reactions with pertechnetate, [TcO 4 ] - , have produced four new low-valent Tc extended metal atom chain (EMAC) complexes with multiple metal-metal bonds. The thermal reaction of potassium pertechnetate with glacial acetic acid, under in-situ hydrogen production from the decomposition of sodium borohydride, yields purple elongated crystals determined to be tetraacetato ditechnetium (II,III) acetate (1), [Tc 2 (O 2 CCH 3 ) 4 (μ-O 2 CCH 3 ] n . Compound 1 was characterized by single crystal X-ray diffraction and its magnetic properties recorded between 10 and 300 K. Single crystal X-ray diffraction analysis of 1 indicates the Tc 2 +5 tetraacetato unit is linked by the carboxylate oxygens of the bridging acetate, similar to known chloride and bromide linkage polymers of composition [Tc 2 (μ-O 2 CCH 3 ) 4 Cl] n , and [Tc 2 (μ-O 2 CCH 3 ) 4 Br] n . Here, using the same synthetic method three similar compounds have been synthesized from propionic, benzoic and pivalic acid.
Salt hydrate-based phase-change materials are considered promising for future heat storage applications in residential heating/cooling systems. Smooth phase transition from the liquid to solid phase and vice versa is essential for effective heat exchanger; however, supercooling in salt hydrates delays the onset of liquid–solid phase transition. We investigate the molecular level mechanism of supercooling in sodium sulfate decahydrate (SSD). SSD is a complex salt hydrate whose properties are governed by electrostatic forces that include pure Coulombic interactions as well as hydrogen bonds. Experimentally, we examine the importance of a nucleator in reducing supercooling temperatures. We investigated the effect of various mass concentrations of a borax nucleator on a decrease of supercooling temperatures. Molecular dynamics simulation techniques are used to obtain a basic understanding of supercooling in SSD. We observe that by introducing borax as a nucleator, there is a decrease in the supercooling temperature before nucleation. Our molecular dynamics simulations show that long-range electrostatics between sodium and sulfate ion pairs and that with polar water molecules is responsible for delayed nucleation in SSD that results in supercooling, and also, dynamics of charged molecules slows down. The lack of crystallization leads to amorphous structures in supercooled SSD.
NpF3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Np3+ is bonded in a 5-coordinate geometry to eleven F1- atoms. There are five shorter (2.40 Å) and six longer (2.70 Å) Np–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to four equivalent Np3+ atoms. In the second F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Np3+ atoms.
IrAl3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ir is bonded in a 5-coordinate geometry to eleven Al atoms. There are a spread of Ir–Al bond distances ranging from 2.48–2.82 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a trigonal planar geometry to three equivalent Ir and six equivalent Al atoms. All Al–Al bond lengths are 2.82 Å. In the second Al site, Al is bonded in a 1-coordinate geometry to four equivalent Ir and seven Al atoms. There are one shorter (2.66 Å) and three longer (2.77 Å) Al–Al bond lengths.
PuH3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Pu3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Pu–H bond distances ranging from 2.15–2.39 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded to four equivalent Pu3+ atoms to form a mixture of corner, edge, and face-sharing HPu4 tetrahedra. In the second H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Pu3+ atoms.
GdH3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Gd3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Gd–H bond distances ranging from 2.15–2.39 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded to four equivalent Gd3+ atoms to form a mixture of corner, edge, and face-sharing HGd4 tetrahedra. In the second H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Gd3+ atoms.
IrSi3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ir4+ is bonded in a 5-coordinate geometry to eleven Si+1.33- atoms. There are a spread of Ir–Si bond distances ranging from 2.49–2.80 Å. There are two inequivalent Si+1.33- sites. In the first Si+1.33- site, Si+1.33- is bonded in a 1-coordinate geometry to four equivalent Ir4+ atoms. In the second Si+1.33- site, Si+1.33- is bonded in a trigonal planar geometry to three equivalent Ir4+ atoms.
CeF3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. Ce3+ is bonded in a 5-coordinate geometry to eleven F1- atoms. There are a spread of Ce–F bond distances ranging from 2.40–2.71 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Ce3+ atoms. In the second F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Ce3+ atoms. In the third F1- site, F1- is bonded in a 1-coordinate geometry to four equivalent Ce3+ atoms.
BiF3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Bi3+ is bonded in a 5-coordinate geometry to eleven F1- atoms. There are a spread of Bi–F bond distances ranging from 2.31–2.67 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Bi3+ atoms. In the second F1- site, F1- is bonded in a distorted single-bond geometry to four equivalent Bi3+ atoms.
PuF3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Pu3+ is bonded in a 5-coordinate geometry to eleven F1- atoms. There are a spread of Pu–F bond distances ranging from 2.36–2.69 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to four equivalent Pu3+ atoms. In the second F1- site, F1- is bonded in a trigonal planar geometry to three equivalent Pu3+ atoms.
LaF3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. La3+ is bonded in a 5-coordinate geometry to eleven F1- atoms. There are five shorter (2.42 Å) and six longer (2.73 Å) La–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to four equivalent La3+ atoms. In the second F1- site, F1- is bonded in a trigonal planar geometry to three equivalent La3+ atoms.
LiP3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Li1+ is bonded in a 11-coordinate geometry to eleven P+0.33- atoms. There are a spread of Li–P bond distances ranging from 2.44–2.87 Å. There are two inequivalent P+0.33- sites. In the first P+0.33- site, P+0.33- is bonded in a 4-coordinate geometry to four equivalent Li1+ and four P+0.33- atoms. There are one shorter (2.30 Å) and three longer (2.70 Å) P–P bond lengths. In the second P+0.33- site, P+0.33- is bonded in a trigonal planar geometry to three equivalent Li1+ and six equivalent P+0.33- atoms.
Ge3Cu is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Cu is bonded in a 3-coordinate geometry to eleven Ge atoms. There are a spread of Cu–Ge bond distances ranging from 2.51–2.95 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to four equivalent Cu and six Ge atoms. There are three shorter (2.85 Å) and three longer (2.95 Å) Ge–Ge bond lengths. In the second Ge site, Ge is bonded in a distorted trigonal planar geometry to three equivalent Cu and six equivalent Ge atoms.
LiAs3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Li1+ is bonded in a distorted trigonal planar geometry to eleven As+0.33- atoms. There are a spread of Li–As bond distances ranging from 2.43–3.13 Å. There are two inequivalent As+0.33- sites. In the first As+0.33- site, As+0.33- is bonded in a 10-coordinate geometry to four equivalent Li1+ and six As+0.33- atoms. There are three shorter (2.80 Å) and three longer (2.99 Å) As–As bond lengths. In the second As+0.33- site, As+0.33- is bonded in a trigonal planar geometry to three equivalent Li1+ and six equivalent As+0.33- atoms.
RbBi3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Rb is bonded in a 11-coordinate geometry to eleven Bi atoms. There are a spread of Rb–Bi bond distances ranging from 3.36–3.71 Å. There are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 1-coordinate geometry to four equivalent Rb and one Bi atom. The Bi–Bi bond length is 3.16 Å. In the second Bi site, Bi is bonded in a trigonal planar geometry to three equivalent Rb atoms.
TbH3 is Sodium arsenide structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Tb3+ is bonded in a 11-coordinate geometry to eleven H1- atoms. There are a spread of Tb–H bond distances ranging from 2.14–2.38 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded in a trigonal planar geometry to three equivalent Tb3+ atoms. In the second H1- site, H1- is bonded to four equivalent Tb3+ atoms to form a mixture of edge, face, and corner-sharing HTb4 tetrahedra.