Raman Spectra Of Trans Research Articles

The infrared and Raman spectra of trans- and cis-tetrachloro-tetramethylbicyclopropylidene

The title compounds trans- and cis-2,2,2′,2′-tetrachloro-3,3,3′,3′-tetramethyl-bicyclopopylidene were synthesized, and their infrared and Raman spectra were recorded. Non-coincidence between the IR and Raman bands of the trans compound suggested C 2h symmetry and a planar ring system. In the cis compound most of the IR and Raman bands coincided and a C 2v symmetry seems likely. The exocyclic C C double bond gave rise to a medium/weak Raman band at 1847 cm −1 in the trans compound. In the cis derivative IR and Raman bands both at 1825 cm −1 were observed. From similarities with related molecules, the ring breathing, the antisymmetric ring stretch, the CCl 2 out-of-phase and in-phase stretch and the out-of-plane ring bending modes have been tentatively assigned for the trans and cis compounds.

Light-induced metastable states in nitrosyl–ruthenium complexes containing ethylenediamine and oxalate ion ligands

The metastable state which is produced by irradiation with the green-blue region of light was studied by IR and other spectroscopic techniques for solid states of newly synthesized nitrosyl–ruthenium complexes; cis-[Ru(Hox)(en)2NO]Cl2·EtOH, trans-[Ru(Hox)(en)2NO]Cl2, cis-K[Ru(ox)2(en)NO]·3H2O, cis-[Ru(Hox)(ox)(en)NO], and cis-K[Ru(ox)2(en)NO] [ox = (CO2)22−]. Continued irradiation at 77 K results in development of a photostationary state in the same way as for sodium nitroprusside. The population of the metastable state molecule in the photostationary state of each sample depends on the irradiation wavelength and reaches a maximum at 441.6 nm which is the shortest wavelength in the present study. A broad absorption band with an absorbance maximum at ≈600 nm is observed for the metastable state of a trans-[Ru(Hox)(en)2NO]Cl2 single crystal. The short wavelength tail of the band is considered to be involved in the photostationary equilibrium under blue light radiation. The metastable state molecules decay to the ground state at temperatures considerably higher than the two metastable molecules (MS1 and MS2) of sodium nitroprusside. The decay temperature of trans-[Ru(Hox)(en)2NO]Cl2, which is defined as the temperature at which the rate constants of the thermal decay becomes 10−3 s−1, is 277 K, which is the highest value reached among the metastable states of nitrosyl complexes reported so far. In the Raman spectra of trans-[Ru(Hox)(en)2NO]Cl2, the Ru-(NO) stretching vibrations are observed at 604 cm−1 and 476 cm−1 for the ground and metastable state molecules, respectively.

Fourier transform infrared and Raman spectra of the green chromium(III) chloride hexahydrate

The Fourier transform infrared and Raman spectra of trans-[CrCl2(H2O)4]Cl·2H2O were studied. The FTIR spectra of a series of partially deuterated compounds were also recorded and served as a basis for assigning some of the observed bands. An interesting temperature dependence was observed for some of the ν(O–D) bands in the FTIR spectra of samples containing isotopically isolated HOD molecules. Multiple bands are observed in the water bending region.

Segmented polyacetylene, (CHD y) x: Electrochemical n-doping studies

Defects involving sp 3 hybridized carbon atoms in the form of (HCD) units have been controllably introduced into trans-(CH) x by chemical methods to produce polymers of the type trans-(CHD y ) x , i.e., [(CH) 1- y − (HCD) y ] x ( y = 0, 0.15 and 0.17), in order to study the nature of these defects and their effect on the electronic and magnetic properties of trans-(CH) x . The effects of these defects on the electrochemical reduction (n-doping) of trans-(CHD y ) x up to 4.0 mol % reduction levels have been studied. The results are consistent with optical and Raman spectra of trans-(CHD y ) x species and are interpreted as showing that: (i) the band gap in trans-(CHD y ) x is essentially unchanged from that in trans-(CH) x because of a small but significant amount of long conjugated sequences remaining in the deuterated polymer; (ii) the maximum density of states near the conduction band edge has moved upwards from the band edge; and (iii) the (HCD) defects are clustered rather than randomly spaced in a given (CHD y ) x chain.

Normal coordinate analyses of 2,4-hexadienes

Measurement and assignment of the i.r. and Raman spectra of trans, trans- and cis, trans-2,4-hexadienes were carried out. The normal coordinate analyses of these two isomers were done to obtain a force field transferable to 1,4-diphenyl- trans, trans-1,3-butadiene and trans- and cis-polyacetylenes.

Raman spectra of trans- and cis-polyacetylenes excited with Nd:YAG laser 1064- and 532-NM pulses

The Nd:YAG laser 1064-nm light and its second harmonic 532-nm light pulses were used to obtain the Raman spectra of trans- and cis-polyacetylenes. The Raman spectra observed with the 1064-nm pulses are essentially the same as those obtained with the cw 1064-nm and 667-nm lines. On the other hand, the Raman spectrum of trans-PA observed with the 532-nm pulses is definitely different from that obtained with the cw 514.5-nm line. This and other experimental results seem to indicate that irradiation with the 532-nm pulses gives rise to shortening of the conjugation length in trans-PA. Various findings can be resonably explained on assuming competition between two opposite processes, namely, the trans-to- cis photoisomerization and the cis-to- trans thermal isomerization. Long cis chains are also photoisomerized with the 532-nm pulses.

Infrared and Raman spectra of trans-[MX 2(H 2 O) 4] + type complex ions (M = Ti(III), V(III) and Cr(III) and X = Cl and Br)

The infrared and low-temperature Raman spectra of Cs 3 VCl 6·4H 2O, CS 2CrCl 5·4H 2O, Cs 2TiCl 5·4H 2O, Cs 2VBr 5·4H 2O, and related compounds have been measured in the region from 4000 to 200 or 100cm −1. Normal coordinate calculations have been carried out on the trans-[MCl 2(H 2O) 4] + structure (M=V(III), Cr(III) and Ti(III)) derived from X-ray analyses of the first two compounds. The presence of the trans-[MX 2(H 2O) 4] + type (XCl and Br) ion in all the compounds studied has been confirmed by the similarity of their vibrational spectra.

The vibrational fine structure of the 1A 2g ← 1A 1g polarized absorption band of trans-[Co(NH 3) 4(CN) 2] +. The excited state geometry

The low temperature polarized absorption, far-infrared, and Raman spectra of trans-[Co(NH 3) 4(CN) 2]Cl (H) and of the deuterated (D) compound

Infrared and Raman spectra of trans N 2F 2

Infrared and Raman spectra of trans N 2F 2 have been measured and the following vibrational assignment is proposed: ν NN = 1522, sν NF = 1010, sδ NF = 600, aν NF = 990, aδ NF = 423 and torsion = 363.5 cm −1