Infrared and Raman polarized spectra of ammonium hydrogen bis(trichloroacetate) single crystal

1985 ◽  
Vol 63 (12) ◽  
pp. 3597-3604 ◽  
Author(s):  
Veneta Videnova-Adrabinska ◽  
Jan Baran ◽  
Henryk Ratajczak ◽  
William J. Orville-Thomas
Keyword(s):  
Hydrogen Bond ◽  
Single Crystal ◽  
Plane Deformation ◽  
Potential Energy Function ◽  
Strong Hydrogen Bond ◽  
Site Symmetry ◽  
Infrared And Raman Spectra ◽  
Out Of Plane ◽  
Ammonium Hydrogen ◽  
Stretching Vibration

The polarized infrared and Raman spectra of ammonium hydrogen bis(trichloroacetate) single crystal have been investigated in the 4000–350 cm−1 and 4000–10 cm−1 range, respectively. The infrared spectra have been measured at room and low temperatures. An assignment of the bands in terms of approximate type of motion is given. The asymmetric stretching vibration, vaOHO, of the strong hydrogen bond gives rise to a very broad infrared absorption, with a maximum around 800 ± 50 cm−1, which is polarized strictly along a tetragonal Z(c) direction of this crystal. For this vibration a correlation field (Davydov or factor group) splitting is not observed. The out-of-plane deformation vibration, γOHO, obeys selection rules for the C2 site symmetry group. This result and also an interpretation of the vC=O vibration strongly suggest that a potential energy function of the strong hydrogen bond has a single symmetric minimum.

PROTONATED γ-PYRONES

1963 ◽  
Vol 41 (2) ◽  
pp. 505-514 ◽  
Author(s):  
Denys Cook
Keyword(s):  
Hydrogen Bond ◽  
Solid State ◽  
Hydrogen Atom ◽  
Oxygen Atom ◽  
Plane Deformation ◽  
Carbonyl Oxygen ◽  
Out Of Plane ◽  
Stretching Vibration ◽  
Stretching Vibrations ◽  
Deformation Modes

The vibrational spectra of several salts of 4-pyrone and 2,6-dimethyl-4-pyrone have been measured in the solid state. Deuterium replacement has been used to identify motions of the hydrogen atom which is located on the carbonyl oxygen atom and forms a hydrogen bond with the anion.Bands due to OH stretching vibrations have been observed from 2086 cm−1 in the HCl salt to 3310 cm−1 in the hexachloroantimonate of 2,6-dimethyl-4-pyrone. In-plane hydrogen-deformation modes of the OH group have been found near 1300 cm−1 with a much smaller range in the different salts than the stretching vibration. For the 4-pyrone salts the OH stretching vibrations were at similar frequencies, and the in-plane hydrogen-deformation frequencies were close to 1340 cm−1. Bands due to the out-of-plane deformation were not observed.Aqueous solutions of 2,6-dimethyl-4-pyrone hydrochloride at various concentrations showed the presence of both protonated and neutral molecules.

Infrared polarized spectra of KH(Cl3CCOO)2 single crystal with a very strong hydrogen bond

1986 ◽  
Vol 145 (1-2) ◽  
pp. 33-43 ◽  
Author(s):  
V. Videnova-Adrabińska ◽  
J. Baran ◽  
H. Ratajczak
Keyword(s):  
Hydrogen Bond ◽  
Single Crystal ◽  
Strong Hydrogen Bond

Effect of cationic substitution on the double-well hydrogen-bond potential in [K1−x(NH4)x]3H(SO4)2proton conductors: a single-crystal neutron diffraction study

2017 ◽  
Vol 73 (5) ◽  
pp. 863-867 ◽  
Author(s):  
R. R. Choudhury ◽  
R. Chitra ◽  
E. V. Selezneva ◽  
I. P. Makarova
Keyword(s):  
Hydrogen Bond ◽  
Neutron Diffraction ◽  
Single Crystal ◽  
Neutron Diffraction Study ◽  
Optical Measurements ◽  
Strong Hydrogen Bond ◽  
Hydrogen Bond Interactions ◽  
Superionic Phase Transition ◽  
The Difference ◽  
Kinetics Of

The structure of the mixed crystal [K1−x(NH4)x]3H(SO4)2as obtained from single-crystal neutron diffraction is compared with the previously reported room-temperature neutron structure of crystalline K3H(SO4)2. The two structures are very similar, as indicated by the high value of their isostructurality index (94.8%). It was found that the replacement of even a small amount (3%) of K+with NH4+has a significant influence on the short strong hydrogen bond connecting the two SO42−ions. Earlier optical measurements had revealed that the kinetics of the superionic transition in the solid solution [K1−x(NH4)x]3H(SO4)2are much faster than in K3H(SO4)2; this reported difference in the kinetics of the superionic phase transition in this class of crystal is explained on the basis of the difference in strength of the hydrogen-bond interactions in the two structures.

Crystal structure of trans-tetraamminebis(isothiocyanato)cobalt(III) acetate-acetic, acid (III)

1980 ◽  
Vol 33 (8) ◽  
pp. 1853 ◽  
Author(s):  
TJ Westcott ◽  
AH White ◽  
AC Willis
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Acetic Acid ◽  
Single Crystal ◽  
Least Squares ◽  
Title Compound ◽  
Site Symmetry ◽  
X Ray Diffraction ◽  
X Ray

The crystal structure of the title compound, trans-[Co(NH3)4(NCS)2] O2CCH3,HO2CCH3, has been determined at 295(1) K by single-crystal X-ray diffraction and refined by least squares to a residual of 0.11 for 300 'observed' reflections. Crystals are orthorhombic, Pbam, a 14.851(9), b 7.068(4), c 7.031(4) Ǻ, Z 2. The cation is centred at the origin of the cell with cobalt site symmetry 2/m, so that only one ammonia and one- half of the N-bonded thiocyanate is crystallographically independent. Co-N(CS) is short (1.91(2) Ǻ); Co-N(H3) being 1.96(2) Ǻ. Only one crystallographically independent acetate species is found, lying close to a coplanar, centrosymmetrically related image to which it is presumably bound by a hydrogen bond (O...O 2.40(4) Ǻ).

Hydrogen bonds in N-(3-chloro-2-benzo[b]thienocarbonyl)- and N-(2-benzo[b]thienocarbonyl)-N'-monosubstituted thioureas

1987 ◽  
Vol 52 (11) ◽  
pp. 2673-2679 ◽  
Author(s):  
Oľga Hritzová ◽  
Peter Kutschy ◽  
Ján Imrich ◽  
Thomas Schöffmann
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Strong Hydrogen Bond ◽  
Cyclic Form ◽  
Thiourea Derivatives

N-(3-Chloro-2-benzo[b]thienocarbonyl)-N'-monosubstituted thiourea derivatives undergo photocyclizations with lower yields than those obtained from analogous N',N'-disubstituted derivatives. This decreased reactivity is caused by the existence of a six-membered cyclic form with the very strong hydrogen bond NH···O=C. The possibility of formation of various conformers has been found with N-(2-benzo[b]thienocarbonyl)-N'-monosubstituted thiourea derivatives as a consequence of the rotation around the C(2)-C(O) connecting line.

scholarly journals Experimental signatures of nodeless multiband superconductivity in a $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ single crystal

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chanhee Kim ◽  
Dilip Bhoi ◽  
Yeahan Sur ◽  
Byung-Gu Jeon ◽  
Dirk Wulferding ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Single Crystal ◽  
Zero Magnetic Field ◽  
Anisotropy Ratio ◽  
Strong Temperature Dependence ◽  
Critical Fields ◽  
Band Theory ◽  
Plane Field ◽  
Low Field ◽  
Out Of Plane

AbstractIn order to understand the superconducting gap nature of a $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ 2H-Pd 0.08 TaSe 2 single crystal with $$T_{c} = 3.13 \text { K}$$ T c = 3.13 K , in-plane thermal conductivity $$\kappa $$ κ , in-plane London penetration depth $$\lambda _{\text {L}}$$ λ L , and the upper critical fields $$H_{c2}$$ H c 2 have been investigated. At zero magnetic field, it is found that no residual linear term $$\kappa _{0}/T$$ κ 0 / T exists and $$\lambda _{\text {L}}$$ λ L follows a power-law $$T^n$$ T n (T: temperature) with n = 2.66 at $$T \le \frac{1}{3}T_c$$ T ≤ 1 3 T c , supporting nodeless superconductivity. Moreover, the magnetic-field dependence of $$\kappa _{0}$$ κ 0 /T clearly shows a shoulder-like feature at a low field region. The temperature dependent $$H_{c2}$$ H c 2 curves for both in-plane and out-of-plane field directions exhibit clear upward curvatures near $$T_c$$ T c , consistent with the shape predicted by the two-band theory and the anisotropy ratio between the $$H_{c2}$$ H c 2 (T) curves exhibits strong temperature-dependence. All these results coherently suggest that $$\hbox {2H-Pd}_{0.08} \hbox {TaSe}_2$$ 2H-Pd 0.08 TaSe 2 is a nodeless, multiband superconductor.

Crystal structure of tamsulosin hydrochloride, C20H29N2O5SCl

2021 ◽  
pp. 1-7
Author(s):  
Nilan V. Patel ◽  
Joseph T. Golab ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Atom ◽  
Powder Diffraction ◽  
Density Functional ◽  
Carbon Chain ◽  
Strong Hydrogen Bond ◽  
Powder Diffraction File ◽  
Ether Oxygen ◽  
Sulfonamide Group

The crystal structure of tamsulosin hydrochloride has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Tamsulosin hydrochloride crystallizes in space group P21 (#4) with a = 7.62988(2), b = 9.27652(2), c = 31.84996(12) Å, β = 93.2221(2)°, V = 2250.734(7) Å3, and Z = 4. In the crystal structure, two arene rings are connected by a carbon chain oriented roughly parallel to the c-axis. The crystal structure is characterized by two slabs of tamsulosin hydrochloride molecules perpendicular to the c-axis. As expected, each of the hydrogens on the protonated nitrogen atoms makes a strong hydrogen bond to one of the chloride anions. The result is to link the cations and anions into columns along the b-axis. One hydrogen atom of each sulfonamide group also makes a hydrogen bond to a chloride anion. The other hydrogen atom of each sulfonamide group forms bifurcated hydrogen bonds to two ether oxygen atoms. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1415.

scholarly journals Characterization and ballistic performance of thin pre-damaged resin-starved aramid-fiber composite panels

2021 ◽  
pp. 004051752110134
Author(s):  
Cerise A Edwards ◽  
Stephen L Ogin ◽  
David A Jesson ◽  
Matthew Oldfield ◽  
Rebecca L Livesey ◽  
...  
Keyword(s):  
Fiber Composite ◽  
Plane Deformation ◽  
Ballistic Impact ◽  
Image Correlation ◽  
Composite Panel ◽  
Composite Panels ◽  
Micro Computed Tomography ◽  
Ballistic Performance ◽  
Low Level ◽  
Out Of Plane

Military personnel use protective armor systems that are frequently exposed to low-level damage, such as non-ballistic impact, wear-and-tear from everyday use, and damage during storage of equipment. The extent to which such low-level pre-damage could affect the performance of an armor system is unknown. In this work, low-level pre-damage has been introduced into a Kevlar/phenolic resin-starved composite panel using tensile loading. The tensile stress–strain behavior of this eight-layer material has been investigated and has been found to have two distinct regions; these have been understood in terms of the microstructure and damage within the composite panels investigated using micro-computed tomography and digital image correlation. Ballistic testing carried out on pristine (control) and pre-damaged panels did not indicate any difference in the V50 ballistic performance. However, an indication of a difference in response to ballistic impact was observed; the area of maximal local out-of-plane deformation for the pre-damaged panels was found to be twice that of the control panels, and the global out-of-plane deformation across the panel was also larger.

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