Synthesis and Crystal Structure of a “High-temperature” Phase of Li[H2NC(O)NH], the Missing Alkali-Metal Ureate

2014 ◽  
Vol 69 (6) ◽  
pp. 651-654
Author(s):  
Hannah Sawinski ◽  
Richard Dronskowski
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Alkali Metal ◽  
Single Crystals ◽  
Liquid Ammonia ◽  
High Temperature Phase ◽  
Monoclinic Space Group ◽  
Temperature Phase ◽  
Synthesis And Crystal Structure ◽  
Bond Lengths

The new salt-like lithium ureate, LiCN2H3O, 1, was synthesized to round up the series of the recently published alkali-metal ureates. Single crystals of 1 were prepared similarly to the previously made ureates of Na-Cs in liquid ammonia. LiCN2H3O crystallizes in the monoclinic space group P21/n with a = 7:5770(9), b = 9:059(1), c = 13:046(2) Å, b = 98:896(2)°, V = 884:8(2)Å3, and Z = 12. The Li+ ions are coordinated by four ureate anions in a distorted tetrahedral manner. As expected, the deprotonation of the urea molecules is reflected by the shape of the anions with two different C-N bond lengths.

ChemInform Abstract: Ferroelectric InMnO3: Growth of Single Crystals, Structure and High-Temperature Phase Transitions.

ChemInform ◽  
2016 ◽  
Vol 47 (40) ◽  
Author(s):  
Maged F. Bekheet ◽  
Ingrid Svoboda ◽  
Na Liu ◽  
Lkhamsuren Bayarjargal ◽  
Elisabeth Irran ◽  
...  
Keyword(s):  
Phase Transitions ◽  
High Temperature ◽  
Single Crystals ◽  
High Temperature Phase ◽  
Temperature Phase

Notizen: Einkristall-Daten der Hochdruck-Hochtemperaturphase von CaSi2 / Structural Refinement of the High Pressure-High Temperature Phase of CaSi2

1982 ◽  
Vol 37 (11) ◽  
pp. 1487-1488 ◽  
Author(s):  
Jürgen Evers ◽  
Gilbert Oehlinger ◽  
Armin Weiss
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Single Crystals ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
Structural Refinement ◽  
Interatomic Distances ◽  
High Pressure High Temperature

The high pressure-high temperature phase of CaSi2 is a representative of the α-ThSi2 type of structure. Single crystals grown at 40 kbar and 1000 °C enabled a structural refinement which leads to interatomic distances Si-Si: 229.9(1) pm (1 × ) and 240.0(1) pm (2 × ), Ca-Si: 309.4(4) pm (4 x ) and 323.9(4) pm (8 × ), Ca-Ca: 400.3(3) pm (4 × ) and 428.3(3) pm (4 × ).

Superprotonic high temperature phase and refinement of the low temperature structure of CsHSeO4

2001 ◽  
Vol 216 (3) ◽  
Author(s):  
M. A. Zakharov ◽  
Sergej I. Troyanov ◽  
Erhard Kemnitz
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Low Temperature ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
Temperature Structure ◽  
Superprotonic Phase

AbstractThe crystal structure of the high temperature superprotonic phase of CsHSeO

Irreversible single-crystal to polycrystal and reversible single-crystal to single-crystal phase transformations in cyanurates

2001 ◽  
Vol 57 (6) ◽  
pp. 791-799 ◽  
Author(s):  
Menahem Kaftory ◽  
Mark Botoshansky ◽  
Moshe Kapon ◽  
Vitaly Shteiman
Keyword(s):  
Phase Transformation ◽  
High Temperature ◽  
Low Temperature ◽  
Single Crystal ◽  
High Temperature Phase ◽  
Monoclinic Space Group ◽  
Temperature Phase ◽  
Space Group ◽  
Reversible Phase ◽  
Low Temperature Phase

4,6-Dimethoxy-3-methyldihydrotriazine-2-one (1) undergoes a single-crystal to single-crystal reversible phase transformation at 319 K. The low-temperature phase crystallizes in monoclinic space group P21/n with two crystallographically independent molecules in the asymmetric unit. The high-temperature phase is obtained by heating a single crystal of the low-temperature phase. This phase is orthorhombic, space group Pnma, with the molecules occupying a crystallographic mirror plane. The enthalpy of the transformation is 1.34 kJ mol−1. The small energy difference between the two phases and the minimal atomic movement facilitate the single-crystal to single-crystal reversible phase transformation with no destruction of the crystal lattice. On further heating, the high-temperature phase undergoes methyl rearrangement in the solid state. 2,4,6-Trimethoxy-1,3,5-triazine (3), on the other hand, undergoes an irreversible phase transformation from single-crystal to polycrystalline material at 340 K with an enthalpy of 3.9 kJ mol−1; upon further heating it melts and methyl rearrangement takes place.

scholarly journals On the high temperature phase transition in Ba(Zr0.20Ti0.80)O3 ceramic

2017 ◽  
Vol 07 (04) ◽  
pp. 1750025 ◽  
Author(s):  
K. P. Chandra ◽  
A. R. Kulkarni ◽  
K. Prasad
Keyword(s):  
Phase Transition ◽  
High Temperature ◽  
Lattice Structure ◽  
High Temperature Phase ◽  
Monoclinic Space Group ◽  
Temperature Phase ◽  
Potential Candidate ◽  
Space Group ◽  
Structure Changes ◽  
Temperature Phase Transition

Temperature dependent X-ray diffraction (XRD) and dielectric properties of perovskite Ba(Zr[Formula: see text]Ti[Formula: see text]O3 ceramic prepared using a standard solid-state reaction process is presented. Along with phase transitions at low temperature, a new phase transition at high temperature (873[Formula: see text]C at 20[Formula: see text]Hz), diffusive in character has been found where the lattice structure changes from monoclinic (space group: [Formula: see text] to hexagonal (space group: [Formula: see text]). This result places present ceramic in the list of potential candidate for intended high temperature applications. The AC conductivity data followed hopping type charge conduction and supports jump relaxation model. The experimental value of [Formula: see text][Formula: see text]pC/N was found. The dependence of polarization and strain on electric field at room temperature suggested that lead-free Ba(Zr[Formula: see text]Ti[Formula: see text]O3 is a promising material for electrostrictive applications.

A new polymorph of Cd3B2O6: synthesis, crystal structure and phase transformation

RSC Advances ◽  
2014 ◽  
Vol 4 (25) ◽  
pp. 13195-13200 ◽  
Author(s):  
Xingwen Zhang ◽  
Hongwei Yu ◽  
Hongping Wu ◽  
Shilie Pan ◽  
Anqing Jiao ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phase Transformation ◽  
High Temperature ◽  
Transformation Process ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
Phase Transformation Process

A new high-temperature phase of Cd3B2O6 (β-Cd3B2O6) has been discovered and the phase transformation process between α- and β-Cd3B2O6 was investigated.

Crystal Structure and Chemical Bonding of the High-Temperature Phase of AgN3.

ChemInform ◽  
2007 ◽  
Vol 38 (17) ◽  
Author(s):  
Carsten L. Schmidt ◽  
Robert Dinnebier ◽  
Ulrich Wedig ◽  
Martin Jansen
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Chemical Bonding ◽  
High Temperature Phase ◽  
Temperature Phase

Crystal Structure of High-Temperature Phase β-NaSrBO3 and Photoluminescence of β-NaSrBO3:Ce3+

2016 ◽  
Vol 55 (13) ◽  
pp. 6487-6495 ◽  
Author(s):  
Huan Yi ◽  
Li Wu ◽  
Liwei Wu ◽  
Lixia Zhao ◽  
Zhiguo Xia ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
High Temperature Phase ◽  
Temperature Phase
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