The crystal and molecular structure of scandium formate

1990 ◽  
Vol 55 (2) ◽  
pp. 426-434 ◽  
Author(s):  
Jindřich Hašek ◽  
Jan Ondráček ◽  
Pavel Karen ◽  
Jaroslav Bauer

The structure of Sc(HCOO)3 was refined up to R = 0.046. The substance crystallizes in the monoclinic system, space group P21/c, a = 10.340(2), b = 6.631(1), c = 9.027(2) Å, β = 98.11(2)°, Z = 4. Scandium atoms are placed in the two symmetrically non-equivalent centres of symmetry thus forming alternating layers parallel to the plane of b,c. All formate oxygens are coordinated to Sc atoms thus forming a three-dimensional net with octahedral coordination of both independent Sc atoms. C-H bonds are oriented in between the nearest oxygens of neighbouring formate groups, but only one contact is sufficiently short to be denoted as the C-H···O hydrogen bond. IR and Raman spectra seem to confirm the differences between formate anions.

1982 ◽  
Vol 47 (10) ◽  
pp. 2623-2632 ◽  
Author(s):  
Viktor Vrábel ◽  
Jan Lokaj ◽  
Ján Garaj ◽  
František Pavelčík

The crystal structure of [Cu(H2O)(en)2][Cu2(CN)3(SeCN)] was solved by single crystal X-ray structural analysis in the triclinic system with a space group of P1 and in the monoclinic system with a space group of C2. In the triclinic system the unit cell has dimensions of a = 0.8445(3), b = 0.7903(3), c = 0.8444(3) nm, α = 119.58(2), β = 118.59(2) and γ = 93.63(3)° and, in the monoclinic system, a = 1.3331(4), b = 0.8670(2), c = 0.8267(3), β = 122.60(2)°. The structure was refined by the least squares method to final value of R = 5.5% in the triclinic system and R = 7.8% in the monoclinic system. The coordination sphere around the Cu(II) atom is square pyramidal, formed of two ethylenediamine molecules and one water molecule. The Cu(I) atoms are tetrahedrally coordinated by bridging SeCN and CN ligands to form infinite three-dimensional chains. The SeCN group is bonded to the Cu(I) atoms through the Se atom at distances of 0.2731(3) and 0.2745(3) nm.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
I Mamarelis ◽  
V Mamareli ◽  
M Kyriakidou ◽  
O Tanis ◽  
C Mamareli ◽  
...  

Abstract Background The atherosclerotic ascending aorta could represent a potential source of emboli or could be an indicator of atherosclerosis in general with high mortality. The mechanism of aneurysm formation and atherosclerosis of the ascending aorta at the molecular level has not yet been clarified. To approach the mechanism of ascending aortic lesions and mineralization at a molecular level, we used the non-destructive FT-IR, Raman spectroscopy, SEM and Hypermicroscope. Methods Six ascending aorta biopsies were obtained from patients who underwent aortic valve replacement (AVR) cardiac surgery. CytoViva (einst inc) hyperspectral microscope was used to obtain the images of ascending aorta. The samples were dissolved in hexane on a microscope glass plate. The FT-IR and Raman spectra were recorded with Nicolet 6700 thermoshintific and micro-Raman Reinshaw (785nm, 145 mwatt), respectively. The architecture of ascending aorta biopsies was obtained by using scanning electron microscope (SEM of Fei Co) without any coating. Results FT-IR and Raman spectra showed changes arising from the increasing of lipophilic environment and aggregate formation (Fig. 1). The band at 1744 cm–1 is attributed to aldehyde CHO mode due to oxidation of lipids. The shifts of the bands of the amide I and amide II bands to lower are associated with protein damage, in agreement with SEM data. The bands at about 1170–1000 cm–1 resulted from the C-O-C of advanced glycation products as result of connecting tissues fragmentations and polymerization. The spectroscopic data were analogous with the lesions observed with SEM and hypermicroscopic images. Conclusions The present innovate molecular structure analysis showed that upon ascending aorta aneurysm development an excess of lipophilic aggregate formation and protein lesions, changing the elasticity of the aorta's wall. The released Ca2+ interacted mostly with carbonate-terminal of cellular protein chains accelerated the ascending aorta calcifications. Figure 1. FT-IR and Raman spectra Funding Acknowledgement Type of funding source: None


1985 ◽  
Vol 40 (7) ◽  
pp. 872-877 ◽  
Author(s):  
W. Kolondra ◽  
W. Schwarz ◽  
J. Weidlein

Abstract Unexpectedly the reaction of SbCl3 with Na(N{SiMe3}2) in a 1:3 molar ratio forms MeSb(N{SiMe3}2)2, I, (Me = CH3) and other trimethylsilyl compounds. The colourless and liquid methylstibane derivative I is monomeric in solution and forms MeSbCl2(N{SiMe3}2)2 (II) on reaction with SO2Cl2. Both new compounds have been characterized by analyses, NMR, IR and Raman spectra. The X-ray structure determination for II shows the monoclinic space group P21/C with 4 monomeric units per cell. The structure was refined to an R-value of 0,052.


1972 ◽  
Vol 27 (10) ◽  
pp. 1127-1130 ◽  
Author(s):  
M. Manewa ◽  
H. P. Fritz

IR and Raman spectra of LiBF4 · n H2O and LiBF4 · n D2O (n = 1, 3) and the normal vibrations of crystal water in the temperature range from 20° to - 125°C are reported. The hydrogen bond strength is correlated with relative force constants and thermogravimetric data.


1971 ◽  
Vol 49 (15) ◽  
pp. 2539-2543 ◽  
Author(s):  
H. Lynton ◽  
J. Passmore

Crystals of difluorochlorine(III)hexafluoroarsenate(V), ClF2AsF6, are monoclinic, space group A2/a, a = 10.676(9), b = 7.673(7), c = 8.064(7) Å, β = 113.40(5)°. The structure was refined by three dimensional least squares methods to R = 0.045 for 185 independent observed reflections. The chlorine atom has two nearest fluorine neighbors at 1.541(14) Å, with a F—Cl—F angle of 103.17(0.70)°, and two longer fluorine bonds at 2.339(14) Å. All five atoms lie in a plane. The arsenic atom is octahedrally coordinated to six fluorine atoms and is connected to two ClF2+ groups via trans fluorine bridges.


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