On the structure and properties of polyamides. XIII. Temperature changes of the vibrational spectra of N-methylacetamide

1964 ◽  
Vol 29 (10) ◽  
pp. 2436-2448 ◽  
Author(s):  
H. Pivcová ◽  
B. Schneider ◽  
J. Štokr ◽  
J. Jakeš
Keyword(s):  
Vibrational Spectra ◽  
Structure And Properties ◽  
Temperature Changes

Bromoselenate(II): Darstellung, Struktur und Eigenschaften von [P(C6H5)4]2SeBr4 und [P(C6H5)4]2Se2Br6 / Bromoselenates(II): Preparation, Structure and Properties of [P(C6H5)4]2SeBr4 and [P(C6H5)4]2Se2Br6

1984 ◽  
Vol 39 (12) ◽  
pp. 1633-1641 ◽  
Author(s):  
Bernt Krebs ◽  
Andreas Schäffer ◽  
Siegfried Pohl
Keyword(s):  
Bond Length ◽  
Vibrational Spectra ◽  
Acetonitrile Solution ◽  
The Novel ◽  
Structure And Properties ◽  
Subsequent Reaction ◽  
Space Group ◽  
X Ray ◽  
Square Planar ◽  
The Mean

The novel anion SeBr42- was prepared by dissociation of SeOBr2 with formation of SeBr2 and subsequent reaction with bromide in acetonitrile solution; it was isolated as the crystalline tetraphenylphosphonium salt. The X-ray structure analysis of [P(C6H 5)4]2SeBr4 (space group P 1̄ , a = 14.190(3), b = 15.125(3), c = 10.383(2) Å , α = 92.69(2), β = 100.89(2), γ = 92.04(2)° Å , V = 2182.2 Å3) shows the structure to contain monomeric SeBr42- anions with a square planar coordination of Se(II). The mean Se -Br bond length in the anion is 2.598 Å .[P(C6H5)4]2Se2Br6 was obtained from the reaction of SeBr4 (which is in equilibrium with SeBr2, Se2Br2, and Br2, in solution) and bromide in acetonitrile. It crystallizes in the space group P 1̄, with a = 1 0 . 9 3 3 ( 4 ) , = 11.154(4), c = 10.344(4) Å , α = 79.26(3), β = 72.63(3), y = 81.35(3)°, γ = 1176.7 Å3 (at -120 °C), and contains a novel type of centrosymmetric Se2Br62- ions with square planar Se-coordination. The mean terminal and bridging Se -Br bond lengths are 2.442 and 2.799 Å , resp. Vibrational spectra are reported and discussed.

Thio-hydroxoanionen des Germaniums: Darstellung, Struktur und Eigenschaften von Na2GeS2(OH)2 · 5 H2O / Thio-hydroxo Anions of Germanium: Preparation, Structure and Properties of Na2GeS2(OH)2 · 5 H2O

1981 ◽  
Vol 36 (11) ◽  
pp. 1400-1406 ◽  
Author(s):  
Bernt Krebs ◽  
Hans-Joachim Wallstab
Keyword(s):  
Hydrogen Bond ◽  
Aqueous Solutions ◽  
Vibrational Spectra ◽  
Sodium Sulfide ◽  
Structure And Properties ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Hydrogen Bond System ◽  
Bond System ◽  
Stretching Vibrations

Abstract Pure thio-hydroxo-germanates can be prepared from aqueous solutions by reactions of stoichiometric amounts of either sodium sulfide and GeO2, or NaOH and GeS2. The preparation of colourless crystalline Na2GeS2(OH)2 · 5 H2O is reported. The compound is characterized by a single-crystal X-ray structure analysis. It is orthorhombic, space group Pbcn, with a = 10.752(2), b= 13.787(2), c = 14.150(2) Å. The structure contains novel monomeric GeS2(OH)22- anions with Ge-S bond distances of 2.150(1) and 2.145(1) Å and with Ge-O lengths of 1.809(3) and 1.815(3) Å. An extensive S ··· HO-and O -HO-hydrogen bond system connects the anions with the octahedrally coordinated Na+ ions. The vibrational spectra are reported. The symmetric GeS2 andGeO2 stretching vibrations in the anion are observed at 415 and 618 cm-1.

On the structure and properties of polyamides. XIX. Vibrational spectra of N-methylacetamide

1965 ◽  
Vol 30 (7) ◽  
pp. 2196-2214 ◽  
Author(s):  
B. Schneider ◽  
A. Hoření ◽  
H. Pivcová ◽  
J. Honzl
Keyword(s):  
Vibrational Spectra ◽  
Structure And Properties

Analysis of Structural Transformations of Fe80Ni10Si5B5 Amorphous Alloy Based on Temperature Changes of Electrical Resistivity

2014 ◽  
Vol 1025-1026 ◽  
pp. 499-503
Author(s):  
Aleksandr Kotvitckii ◽  
Galina Kraynova ◽  
Anatoly Frolov ◽  
Vitaly Ivanov ◽  
Vladimir Plotnikov
Keyword(s):  
Electrical Resistivity ◽  
Amorphous Alloy ◽  
Structural Transformations ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Calorimetric Analysis ◽  
Temperature Changes ◽  
X Ray ◽  
Higher Temperature ◽  
Magnetic Nature

In this paper the change of electrical resistivity of the amorphous alloy Fe80Ni10Si5B5during heat treatment is investigated. Parallel studies by magnetometry technique, X-ray diffraction and calorimetric analysis were used to interpret the nature of the changes in the structure and properties of the alloy during annealing. These features are related with magnetic nature of the alloy and crystallization at a higher temperature.

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