FT-near-IR and FT-IR Studies of Cis-9-Octadecen-1-ol: Molar Absorption Coefficient of a Band Due to the First Overtone of the Stretching Mode of the Terminal OH Group and Comparison of Anharmonicity of an OH Stretching Mode among the Monomeric and Associated Species

1995 ◽  
Vol 49 (11) ◽  
pp. 1661-1668 ◽  
Author(s):  
Yongliang Liu ◽  
Hisashi Maeda ◽  
Yukihiro Ozaki ◽  
Mirosław A. Czarnecki ◽  
Masao Suzuki ◽  
...  
Keyword(s):  
Absorption Coefficient ◽  
Near Infrared ◽  
Molar Absorption Coefficient ◽  
Open Chain ◽  
Oh Groups ◽  
Ir Studies ◽  
Near Ir ◽  
Ft Ir ◽  
Self Association ◽  
Associated Species

Fourier transform near-infrared (FT-near-IR) and FT-IR spectra have been measured for cis-9-octadecen-1-ol in CCl4 solutions at various concentrations and temperatures partly to investigate its self-association and partly to explore its near-IR spectrum. Both spectra have demonstrated the appearances of bands due to free terminal OH groups of the linear dimer (open-chain dimer) and oligomer of the alcohol. They are observed at 3621 and 7070 cm−1 in the IR and near-IR regions, whose frequencies are lower by 16 and 34 cm−1, respectively, than those of the corresponding bands due to a free OH group of the monomer. The spectral changes in both regions suggest that (1) at concentrations below 0.10 M, the alcohol exists mostly as the monomer and dimer, and with increasing temperature the dimer dissociates into the monomer; and (2) as the concentration is increased, it associates to form aggregates (such as tetramer), and with temperature increase the aggregates dissociate into the dimer and monomer. The molar absorption coefficient of the band due to the first overtone of the stretching mode of the terminal OH groups has been determined to be 0.139 dm3 mol−1 cm−1. It is approximately 8% of that of the first overtone of the monomeric OH group (1.63 dm3 mol−1 cm−1). The anharmonicity of an OH stretching mode of the alcohol has been investigated for various OH groups, free, terminal, and hydrogen-bonded, by comparing the frequencies of the bands due to the OH stretching modes with those of the bands due to the corresponding first overtones. The anharmonicity of the stretching mode of the terminal OH groups of the associated species is very similar to that for the free OH group of the monomer.

Phthalocyanines-based photoacoustic contrast agents for imaging and theranostics

2021 ◽  
Author(s):  
Bing-De Zheng ◽  
Jing Ye ◽  
Yayan Huang ◽  
Meitian Xiao
Keyword(s):  
Absorption Coefficient ◽  
Contrast Agents ◽  
Near Infrared ◽  
Organic Dye ◽  
Molar Absorption Coefficient

Phthalocyanine, as an organic dye, has attracted much attention due to its high molar absorption coefficient in the near-infrared (NIR) region. It is precisely because of this advantage that phthalocyanine...

scholarly journals The Temperature-Dependent Adsorption Behaviour of Benzene Molecules in ZSM-5 Zeolite Pores: TPD and FT-IR Spectroscopy Studies

2005 ◽  
Vol 23 (2) ◽  
pp. 95-107 ◽  
Author(s):  
Arati Sahasrabudhe ◽  
Salil Varma ◽  
Narendra M. Gupta
Keyword(s):  
Benzene Molecule ◽  
Hydroxyl Groups ◽  
Fixed Amount ◽  
Oh Groups ◽  
Ir Studies ◽  
Ft Ir ◽  
Temperature Programmed ◽  
Spectroscopy Studies ◽  
Ir Spectroscopic

Temperature-programmed desorption (TPD) and in situ Fourier-transform infrared (FT-IR) spectroscopic methods were employed to investigate the effect of loading and sample temperature on the state of benzene molecules inside the channels of NaZSM-5 zeolite. TPD profiles revealed the existence of at least three distinct states of benzene adsorption, characterized by desorption peak maxima at ca. 120°C, 170°C and 220°C, respectively. Based on the growth behaviour of these bands, it is suggested that the benzene molecules occupy sinusoidal channels, straight channels and external surfaces, in that order. A reverse trend was observed during the subsequent flushing of the sample at varying temperatures. A virtually fixed amount of benzene was occluded at these three locations, depending upon the loading. The FT-IR studies revealed that the benzene molecule exists in a compressed state in the zeolitic channels, with the molecular clusters formed in the process dispersing only at temperatures above 150°C. For initial benzene loadings of up to ca. 1.5 molecules/unit cell, the spectrum obtained showed that in the O—H stretch region the bridge-bonded OH groups and hydroxyl groups associated with the internal zeolitic channels were perturbed simultaneously. The results show that even for a loading lower than necessary for saturation, a considerable amount of benzene remains condensed at the external surface of ZSM-5 zeolite.

Carbon dioxide in pollucite, a feldspathoid with the ideal composition (Cs, Na)16Al16Si32O96·nH2O

2012 ◽  
Vol 76 (4) ◽  
pp. 903-911 ◽  
Author(s):  
F. Bellatreccia ◽  
G. Della Ventura ◽  
G. D. Gatta ◽  
M. Cestelli Guidi ◽  
S. Harley
Keyword(s):  
Absorption Coefficient ◽  
Single Crystal ◽  
Near Infrared ◽  
Secondary Ion Mass Spectrometry ◽  
Infrared Region ◽  
Sharp Peak ◽  
Molar Absorption Coefficient ◽  
X Ray Diffraction ◽  
Bending Vibration ◽  
Ideal Composition

AbstractWe report a single-crystal Fourier-transform infrared (FTIR) study of a sample of pollucite from Maine, USA. Prior to our work, the sample had been characterized by single-crystal X-ray diffraction, neutron diffraction and electron-probe microanalysis. It is cubicIa3d, with a crystal-chemical formula Na1.93(Cs10.48Rb0.31K0.04)Σ=10.83(Al14.45Si33.97)Σ=48.42O96·3.92H2O, and an H2O content, determined by thermogravimetric analysis, of 1.6 wt.%. The single-crystal FTIR spectrum has a doublet of intense bands at 3670 and 3589 cm–1, which are assigned to the ν3and ν1stretching modes of the H2O molecule, respectively. A very intense and sharp peak at 1620 cm–1is assigned to the ν2bending vibration. In the near-infrared region there is a relatively intense peak at 5270 cm–1, which is assigned to a combination (ν2+ ν3) mode of H2O, and a weak but well defined doublet at 7118 and 6831 cm–1, which is assigned to the first overtones of the fundamental stretching modes. A relatively weak but extremely sharp peak at 2348 cm–1shows that the pollucite contains CO2molecules in structural cavities. Mapping the sample using FTIR indicates that both H2O and CO2are homogeneously distributed. Secondary ion mass spectrometry yielded an average CO2content of 0.09±0.02 wt.%. On the basis of this value, we determined the integrated molar absorption coefficient for the spectroscopic analysis of CO2in pollucite to be εiCO2= 11,000±3000 l mol–1cm–2; the linear molar absorption coefficient for the same integration range is εlCO2= 1600±500 l mol–1cm–1.

Characterization of the Interaction of Amphotericin B with Cholesteryl Trifluoromethylphenyl-Carbamate by UV-Visible Spectroscopy

2008 ◽  
Vol 59 (3) ◽  
pp. 297-299
Author(s):  
Loredana Elena Vijan ◽  
Carmen Mihaela Topala
Keyword(s):  
Absorption Coefficient ◽  
Amphotericin B ◽  
Molar Absorption Coefficient ◽  
Polyene Antibiotic ◽  
Visible Spectroscopy ◽  
Dimerization Constant ◽  
Cooperativity Effects ◽  
Uv Visible ◽  
Self Association

Amphotericin B, a polyene antibiotic, self-associates in ethanol. The self-association of antibiotic has characterized by UV-visible spectroscopy. Starting from a simple dimerization model and using different methods described in literature, one determined the molar absorption coefficient of monomer, the molar absorption coefficient of dimer and the dimerization constant. The binding of amphotericin B to cholesteryl trifluoromethylphenyl-carbamate has investigated using absorbance measurements and the results have rationalized in terms of literature models, taking into account both 1:1 drug-sterol system and cooperativity effects. The binding constant of amphotericin B to cholesteryl trifluoromethylphenyl-carbamate has determined using Benesi-Hildebrand, Scott and Scatchard methods.

Chemical Mapping in the Mid- and Near-IR Spectral Regions by Hadamard Transform/FT-IR Spectrometry

1997 ◽  
Vol 51 (4) ◽  
pp. 477-486 ◽  
Author(s):  
M. K. Bellamy ◽  
A. N. Mortensen ◽  
R. M. Hammaker ◽  
W. G. Fateley
Keyword(s):  
Near Infrared ◽  
Signal To Noise Ratio ◽  
Hadamard Transform ◽  
Chemical Mapping ◽  
Ir Spectrometry ◽  
Near Ir ◽  
Heterogeneous Samples ◽  
Infrared Spectral ◽  
Ft Ir ◽  
Data Acquisition And Processing

A movable two-dimensional (2D) Hadamard encoding mask is obtained and combined with conventional FT-IR spectrometers for use in both the mid- and near-infrared spectral regions. Chemical maps and spectra of individual pixels of the maps can be obtained from heterogeneous samples by using this combination of a move-able 2D Hadamard encoding mask and an FT-IR spectrometer. We call the procedure Hadamard transform/FT-IR spectrometry. Spectra of usable signal-to-noise ratio and reliable chemical maps are obtained in reasonable data acquisition and processing time.

The Investigation of the Neopluramycin � DNA System by UV-visible Spectroscopy

2008 ◽  
Vol 59 (9) ◽  
Author(s):  
Loredana Elena V�jan
Keyword(s):  
Absorption Coefficient ◽  
Binding Constant ◽  
The Self ◽  
Molar Absorption Coefficient ◽  
Water Mixture ◽  
Visible Spectroscopy ◽  
Dimerization Constant ◽  
Calf Thymus ◽  
Uv Visible ◽  
Self Association

The self-association of neopluramycin and the binding of this drug to calf thymus DNA were investigated by using UV-visible spectroscopy. This classical pluramycin antibiotic self-associates in 1:1 ethanol - water mixture. Starting from a simple dimerization model, the molar absorption coefficient of monomer, the molar absorption coefficient of dimer and the dimerization constant were determined. The binding constant of neopluramycin to DNA was determined using Wolfe and Scatchard methods.

An Application of near Infrared and Mid-Infrared Spectroscopy to the Study of Uranyl Selenite Minerals: Derriksite, Demesmaekerite, Guilleminite and Haynesite

2008 ◽  
Vol 16 (5) ◽  
pp. 455-469 ◽  
Author(s):  
Ray L. Frost ◽  
B. Jagannadha Reddy ◽  
Marilla J. Dickfos
Keyword(s):  
Near Infrared ◽  
Nir Spectroscopy ◽  
Uranyl Ion ◽  
Absorption Feature ◽  
Significant Shift ◽  
Bending Vibrations ◽  
Oh Groups ◽  
Ir Studies ◽  
Geologic Materials ◽  
Bending Modes

The near infrared (NIR) spectra of the natural uranyl selenite minerals that include derriksite, demesmaekerite, guilleminite and haynesite are examined as a potential indicator of uranium occurring geologic materials at the earth's surface. NIR analysis, complimented with mid-IR studies, was used to investigate the co-ordination of UO22+ and Cu2+ in the uranyl selenites. Bands obtained from the infrared spectra of selenites are interpreted in terms of the stretching vibrations of uranyl, selenite units and OH groups and bending modes. NIR spectra of the uranyl selenite minerals exhibit distinctive characteristics of uranyl ion (UO2)2+ absorptions over the range of 11,500–8000 cm−1. The high- range NIR spectrum of Cu-bearing uranyl derriksite is resolved into two bands, UO22+ 8070 cm−1 and Cu2+ 7175 cm−1. The effect of lead in demesmaekerite leads to distortion of the spectrum and the NIR bands are observed for uranyl ion at 11,305 cm−1 and 8475 cm−1 and for Cu2+ at 7430 cm−1. The δ U–OH bending vibrations are characterised by a strong absorption feature centred at 1015 cm−1 in haynesite. A significant shift for UOH bending vibrations and the absence of ν1 and ν3 vibrations of UO22+ at the expense of Cu2+ are reflected in the spectrum of derriksite. The complexity of bands with shifts to low wavenumbers could take place due to the additional cations of Pb and Cu in the structure of demesmaekerite. NIR spectroscopy has proven to be a most useful tool for the identification of and distinction between different uranyl selenite minerals.

Plasmon-assisted interaction of Si with light, for cancer hyperthermia and electromagnetic energy harvest

2020 ◽  
Vol 92 (2) ◽  
pp. 20101
Author(s):  
Behnam Kheyraddini Mousavi ◽  
Morteza Rezaei Talarposhti ◽  
Farshid Karbassian ◽  
Arash Kheyraddini Mousavi
Keyword(s):  
Silicon Nanowires ◽  
Metallic Nanoparticles ◽  
Near Infrared ◽  
Optical Transition ◽  
Electromagnetic Energy ◽  
Energy Harvest ◽  
Absorption Enhancement ◽  
Ir Absorption ◽  
Absorption Mechanism ◽  
Near Ir

Metal-assisted chemical etching (MACE) is applied for fabrication of silicon nanowires (SiNWs). We have shown the effect of amorphous sheath of SiNWs by treating the nanowires with SF6 and the resulting reduction of absorption bandwidth, i.e. making SiNWs semi-transparent in near-infrared (IR). For the first time, by treating the fabricated SiNWs with copper containing HF∕H2O2∕H2O solution, we have generated crystalline nanowires with broader light absorption spectrum, up to λ = 1 μm. Both the absorption and photo-luminescence (PL) of the SiNWs are observed from visible to IR wavelengths. It is found that the SiNWs have PL at visible and near Infrared wavelengths, which may infer presence of mechanisms such as forbidden gap transitions other can involvement of plasmonic resonances. Non-radiative recombination of excitons is one of the reasons behind absorption of SiNWs. Also, on the dielectric metal interface, the absorption mechanism can be due to plasmonic dissipation or plasmon-assisted generation of excitons in the indirect band-gap material. Comparison between nanowires with and without metallic nanoparticles has revealed the effect of nanoparticles on absorption enhancement. The broader near IR absorption, paves the way for applications like hyperthermia of cancer while the optical transition in near IR also facilitates harvesting electromagnetic energy at a broad spectrum from visible to IR.

scholarly journals Anisotropies of the infrared background and primordial galaxies

2006 ◽  
Vol 2 (14) ◽  
pp. 266-266
Author(s):  
Asantha R. Cooray
Keyword(s):  
Galaxy Formation ◽  
Near Infrared ◽  
Imaging Data ◽  
Near Ir ◽  
Infrared Background ◽  
Cosmic Infrared Background ◽  
Galactic Background

AbstractWe discuss anisotropies in the near-IR background between 1 to a few microns. This background is expected to contain a signature of primordial galaxies. We have measured fluctuations of resolved galaxies with Spitzer imaging data and we are developing a rocket-borne instrument (the Cosmic Infrared Background ExpeRiment, or CIBER) to search for signatures of primordial galaxy formation in the cosmic near-infrared extra-galactic background.

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