scholarly journals Solid-State Isomerization and Infrared Band Strengths of Two Conformational Isomers of Cyclopropanecarboxaldehyde, a Candidate Interstellar Molecule

2019 ◽  
Vol 3 (7) ◽  
pp. 1182-1188 ◽  
Author(s):  
Reggie L. Hudson ◽  
Falvia M. Coleman
Keyword(s):  
Solid State ◽  
Infrared Band ◽  
Interstellar Molecule ◽  
Conformational Isomers

Structural studies of organoboron compounds. XXXII. 5,5-Difluoro-2,2-pentamethylene-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene and 2,2-pentamethylene-5,5-diphenyl-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene

1988 ◽  
Vol 66 (10) ◽  
pp. 2621-2630 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Mahmood Tajerbashi ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Solid State ◽  
Physical Properties ◽  
Least Squares ◽  
Crystal Structures ◽  
Direct Methods ◽  
Structural Studies ◽  
Full Matrix ◽  
Space Group ◽  
Bond Lengths ◽  
Conformational Isomers

Details of the syntheses, physical properties, and crystal structures of the title compounds are reported. Crystals of 5,5-difluoro-2,2-pentamethylene-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene are triclinic, a = 6.1576(3), b = 11.2651(3), c = 10.8118(3) Å, α = 109.747(3), β = 105.807(4), γ = 92.976(4)°, Z = 2, space group [Formula: see text], and those of 2,2-pentamethylene-5,5-diphenyl-1,4,6-trioxa-3a-azonia-5-borata-1,2,3,4,5,6-hexahydrobenzo[h]azulene are monoclinic, a = 9.8549(6), b = 10.9242(6), c = 41.263(2) Å, β = 92.717(6)°, Z = 8, space group P21/n. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.045 and 0.042 for 2344 and 4248 reflections with I ≥ 3σ(I), respectively. The molecules were both found to possess a seven-membered chelate structure, the O,O-chelatїng ligand being strongly bound to the X2B moiety. Two conformational isomers of the X = Ph compound were found in the solid state. The 2-oxazoline N-oxide moieties present in both compounds are the first to be structurally characterized. Important mean libration-corrected bond lengths are: O—B = 1.491 and F—B = 1.387 Å for X = F; O—B = 1.511 and C—B = 1.620 Å for X = Ph.

Copper(II) complexes of o-hydroxyarylcarbonyl compounds

1968 ◽  
Vol 21 (3) ◽  
pp. 617 ◽  
Author(s):  
DP Graddon ◽  
GM Mockler
Keyword(s):  
Solid State ◽  
Chelate Ring ◽  
Magnetic Moments ◽  
Equilibrium Constants ◽  
Ligand Field ◽  
Infrared Band ◽  
Planar Structures ◽  
Square Planar ◽  
Inductive Effects ◽  
Ligand Field Spectra

A series of copper(11) complexes has been prepared of the type CuL2Bn, where L is an o-hydroxy-aryl-, or naphthyl-, aldehyde, ketone, or ester, B is water or 4-methylpyridine, and n = 0, 1, or 2. All these complexes have a strong infrared band in the region 1600-1660 cm-l, showing that the oxygen atoms in the chelate ring are non-equivalent ; their magnetic moments fall in the range usual for copper(11) compounds. Equilibrium constants determined for the addition of one molecule of 4-methylpyridine to the anhydrous compounds in chloroform solutions fall in the range 0.5 < k < 40 and are comparable to the constant for the addition of 4-methylpyridine to bis(acetylacetonato)copper(11) (b 2.7). Increased stability of the adducts can be associated with the inductive effects of ligand substituents. Ligand field spectra in the solid state and in solution closely resemble those of corresponding bis(acetylaoetonato)copper(11) complexes and provide evidence for square-planar structures of the anhydrous complexes and square-pyramidal structures of the 1 : 1 adducts with 4-methylpyridine or water. No evidence is available for the structures of 1 : 2 adduots which may be formed in solutions in 4-methylpyridine; these solutions are unstable, but the nature of the slow reactions which occur in these solutions is not known.

scholarly journals Development Progress of 3–5 μm Mid-Infrared Lasers: OPO, Solid-State and Fiber Laser

2021 ◽  
Vol 11 (23) ◽  
pp. 11451
Author(s):  
Tingwei Ren ◽  
Chunting Wu ◽  
Yongji Yu ◽  
Tongyu Dai ◽  
Fei Chen ◽  
...  
Keyword(s):  
Solid State ◽  
Fiber Laser ◽  
Molecular Spectroscopy ◽  
Infrared Laser ◽  
Rare Earth Ions ◽  
Parametric Oscillation ◽  
Infrared Lasers ◽  
Infrared Band ◽  
Mid Infrared ◽  
Advantages And Disadvantages

A 3–5 μm mid-infrared band is a good window for atmospheric transmission. It has the advantages of high contrast and strong penetration under high humidity conditions. Therefore, it has important applications in the fields of laser medicine, laser radar, environmental monitoring, remote sensing, molecular spectroscopy, industrial processing, space communication and photoelectric confrontation. In this paper, the application background of mid-infrared laser is summarized. The ways to realize mid-infrared laser output are described by optical parametric oscillation, mid-infrared solid-state laser doped with different active ions and fiber laser doped with different rare earth ions. The advantages and disadvantages of various mid-infrared lasers are briefly described. The technical approaches, schemes and research status of mid-infrared lasers are introduced.

Investigations of the assignment of the 2190 cm−1 infrared band in polyfumaronitrile

1985 ◽  
Vol 63 (7) ◽  
pp. 1960-1966 ◽  
Author(s):  
Kenneth L. Gallaher ◽  
Dorothy Lukco ◽  
Jeanette G. Grasselli
Keyword(s):  
Solid State ◽  
Infrared Band ◽  
Spectral Similarity ◽  
H Nmr

Polyfumaronitrile exhibits a band at 2190 cm−1 which has at various times been associated with a β-aminonitrile, an iminonitrile, or with C=N in an α-pyrrolenine ring. This band is of particular interest because it sometimes appears in degraded polyacrylonitrile and nitrile-containing resins. The previous conflicting assignments were made on the basis of ir, uv, 1H nmr, and chemical results. This paper reports new infrared, esr, and solid-state carbon nmr results which indicate that the 2190 cm−1 band is most likely due to a β-aminonitrile functionality. The close spectral similarity with 3-amino crotonitrile is particularly noted. A mechanism is proposed which would explain the presence of such a nitrile in polyfumaronitrile.

Studies in the stereochemistry of zinc(II). V. Zinc complexes with N-alkylsalicylaldimines

1967 ◽  
Vol 20 (5) ◽  
pp. 877 ◽  
Author(s):  
GE Batley ◽  
DP Graddon
Keyword(s):  
Solid State ◽  
Infrared Spectra ◽  
Spectroscopic Studies ◽  
Zinc Complexes ◽  
Ultraviolet Region ◽  
Concentrated Solutions ◽  
Infrared Band ◽  
Phenolic Oxygen ◽  
Ultraviolet Reflectance ◽  
Solid Compounds

Bis(N-alkylsalicylaldiminato)zinc(II) complexes are monomeric and 4- coordinate in dilute solutions in toluene but some association is observed in concentrated solutions in diphenylamine. Spectroscopic studies in the ultraviolet region show that only the methyl and ethyl homologues form 5-coordinate pyridine adducts even in pyridine solutions. Only the methyl homologue forms a pyridine adduct stable enough to be isolated, and only this homologue forms a 5-coordinate dimer in the solid state. The ultraviolet reflectance spectra and infrared spectra of the solid compounds can be used to distinguish those compounds in which some or all of the phenolic oxygen atoms are bridging: such bridging is accompanied by a splitting of the ultraviolet absorption near 370 mμ and a shift of a very sharp infrared band from 1530 to 1550 cm-1. This band is tentatively assigned to the phenolic C-O stretching mode.

Preparation of Thin Cadmium Telluride Samples for Electron Microscope Studies

1974 ◽  
Vol 32 ◽  
pp. 548-549
Author(s):  
T. J. Magee ◽  
J. Peng ◽  
J. Bean
Keyword(s):  
Electron Microscope ◽  
Sulfuric Acid ◽  
Solid State ◽  
Sample Preparation ◽  
Cadmium Telluride ◽  
Potassium Dichromate ◽  
Optical Components ◽  
The Past ◽  
Solid State Devices

Cadmium telluride has become increasingly important in a number of technological applications, particularly in the area of laser-optical components and solid state devices, Microstructural characterizations of the material have in the past been somewhat limited because of the lack of suitable sample preparation and thinning techniques. Utilizing a modified jet thinning apparatus and a potassium dichromate-sulfuric acid thinning solution, a procedure has now been developed for obtaining thin contamination-free samples for TEM examination.

The Collagenic Molecular Structural Unit of Solid State Complexes

1971 ◽  
Vol 29 ◽  
pp. 478-479
Author(s):  
Kenneth M. Richter ◽  
John A. Schilling
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Structural Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Naoh Treatment

The structural unit of solid state collagen complexes has been reported by Porter and Vanamee via EM and by Cowan, North and Randall via x-ray diffraction to be an ellipsoidal unit of 210-270 A. length by 50-100 A. diameter. It subsequently was independently demonstrated by us in dog tendon, dermis, and induced complexes. Its detailed morphologic, dimensional and molecular weight (MW) aspects have now been determined. It is pear-shaped in long profile with m diameters of 57 and 108 A. and m length of 263 A. (Fig. 1, tendon, KMnO4 fixation, Na-tungstate; Fig. 2a, schematic of unit in long, C, and x-sectional profiles of its thin, xB, and bulbous, xA portions; Fig. 2b, tendon essentially unmodified by ether and 0.4 N NaOH treatment, Na-tungstate). The unit consists of a uniquely coild cable, c, of ṁ 22.9 A. diameter and length of 2580-3316 A. The cable consists of three 2nd-strands, s, each of m 10.6 A.

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