UV-Vis-NIR absorption spectra of lanthanide oxides and fluorides

Absorption spectra of [Re(CO)3(imidazole)(phenanthroline)]+ were computed using TD-DFT with QM/MM, frozen-density embedding, and implicit solvation models.

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Samarium Ions Concentration Dependent Optical Enhancement in Phosphate Glass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1107.449 ◽

2015 ◽

Vol 1107 ◽

pp. 449-453

Author(s):

Ramli Arifin ◽

Lee Pei San ◽

Md Rahim Sahar ◽

Sib Krishna Ghoshal ◽

Khaidzir Hamzah

Keyword(s):

Rare Earth ◽

Chemical Composition ◽

Absorption Spectra ◽

Phosphate Glass ◽

Emission Spectra ◽

Photonic Devices ◽

Phosphate Glasses ◽

Significant Enhancement ◽

Melt Quenching ◽

Nir Absorption

Glasses activated rare earth (RE) ions are demanding for photonic devices. Optimization of rare earth dopants, chemical composition of glass former and modifier decides spectra features. We synthesize a series of glass having composition (50-x)P2O5 - 30Li2O - 20Na2O - (x)Sm2O3, where x = 0 to 2.0 mol% (optimizing RE concentration) via melt-quenching technique. The effects of Sm2O3 concentration on significant enhancement of absorption and luminescence are scrutinized. The UV-Vis-NIR absorption spectra reveal ten band and the emission spectra exhibit four peaks specific to the dopant. The results suggest that samarium doped phosphate glasses are potential for laser and other applications.

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Modification of Layered Double Hydroxides Using First-Row Transition Metals for Superior UV-Vis-NIR Absorption and the Influence of the Synthesis Method Used

10.26434/chemrxiv.11815443 ◽

2020 ◽

Author(s):

Bianca Gevers ◽

Sajid Naseem ◽

Charles Sheppard ◽

Andreas Leuteritz ◽

Johan Labuschagne

Keyword(s):

Transition Metals ◽

Absorption Spectra ◽

Layered Double Hydroxides ◽

Synthesis Method ◽

Adequate Explanation ◽

Standard Methods ◽

Absorption Intensity ◽

Synthesis Conditions ◽

Nir Absorption ◽

Double Hydroxides

<div>Layered double hydroxides (LDHs) with high and tailorable UV-Vis-NIR absorption were prepared through transition</div><div>metal (TM) modification. The synthesis method used and amount of TM present were found to influence the UV-Vis-</div><div>NIR absorption intensity, -range, and the optical bandgap.</div><div><div>It was found that the incorporation of TMs in MgAl-LDH results in the existence of a "UV-Vis-NIR absorption fingerprint", the intensity of which can be tuned by the amount of TM present. There also exist differences in the UV-Vis-NIR absorption spectra and bandgaps obtained for MgAl-LDH synthesised using different synthesis conditions and methods, but these are not as visible when including transition metals. Further, the materials exhibit very complex spectra for which adequate explanation is lacking in literature. Finally, standard methods to determine the bandgap of materials, did not give conclusive results for all materials, only for some, and indicate that some of the materials might have multiple different transition types.</div></div>

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Conductivity Characteristics and Vis-NIR Absorption Spectra of Polypyrrole Films at Higher Temperatures

Polymer Journal ◽

10.1295/polymj.28.559 ◽

1996 ◽

Vol 28 (7) ◽

pp. 559-562 ◽

Cited By ~ 2

Author(s):

Yongfang Li ◽

Kenichi Imaeda ◽

Hiroo Inokuchi

Keyword(s):

Absorption Spectra ◽

Polypyrrole Films ◽

Nir Absorption

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Front Cover: Palladium Complexes of Carbazole-Based Chalcogenaisophlorins: Synthesis, Structure, and Solid-State NIR Absorption Spectra (ChemPlusChem 12/2017)

ChemPlusChem ◽

10.1002/cplu.201700472 ◽

2017 ◽

Vol 82 (12) ◽

pp. 1365-1365

Author(s):

Chihiro Maeda ◽

Kazuto Takaishi ◽

Tadashi Ema

Keyword(s):

Solid State ◽

Absorption Spectra ◽

Palladium Complexes ◽

Front Cover ◽

Nir Absorption

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Utilization of cloud-point extraction for colorimetric determination of trace amounts of thorium(iv) in real samples

RSC Advances ◽

10.1039/c5ra08806b ◽

2015 ◽

Vol 5 (64) ◽

pp. 52095-52100 ◽

Cited By ~ 13

Author(s):

Alaa S. Amin ◽

Mohammed A. Kassem ◽

Talaat Y. Mohammed

Keyword(s):

Cloud Point ◽

Absorption Spectra ◽

Cloud Point Extraction ◽

Colorimetric Determination ◽

Real Samples ◽

P Absorption

Absorption spectra for 0.5 μg mL−1 without CPE and 5.0 ng mL−1 complexed with DMPAHPD using CPE at pH 7.8.

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How to remove the influence of trace water from the absorption spectra of SWNTs dispersed in ionic liquids

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.2.69 ◽

2011 ◽

Vol 2 ◽

pp. 653-658 ◽

Cited By ~ 6

Author(s):

Juan Yang ◽

Daqi Zhang ◽

Yan Li

Keyword(s):

Ionic Liquids ◽

Absorption Spectra ◽

Pure Water ◽

High Concentration ◽

Quantitative Characterization ◽

Intrinsic Structure ◽

Nir Absorption ◽

Walled Carbon Nanotubes ◽

Trace Water

Single-walled carbon nanotubes (SWNTs) can be efficiently dispersed in the imidazolium-based ionic liquids (ILs), at relatively high concentration, with their intrinsic structure and properties retained. Due to the hygroscopicity of the ILs, water bands may be introduced in the absorption spectra of IL-dispersed SWNTs and cause problems in spectral deconvolution and further analysis. In order to remove this influence, a quantitative characterization of the trace water in [BMIM]+[PF6]− and [BMIM]+[BF4]− was carried out by means of UV–vis-NIR absorption spectroscopy. A simple yet effective method involving spectral subtraction of the water bands was utilized, and almost no difference was found between the spectra of the dry IL-dispersed SWNT samples treated under vacuum for 10 hours and the spectra of the untreated samples with subtraction of the pure water spectrum. This result makes it more convenient to characterize SWNTs with absorption spectra in the IL-dispersion system, even in the presence of trace amount of water.

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NIR Absorbance Characteristics of Deoxynivalenol and of Sound and Fusarium-Damaged Wheat Kernels

Journal of Near Infrared Spectroscopy ◽

10.1255/jnirs.846 ◽

2009 ◽

Vol 17 (4) ◽

pp. 213-221 ◽

Cited By ~ 44

Author(s):

Kamaranga H.S. Peiris ◽

Michael O. Pumphrey ◽

Floyd E. Dowell

Keyword(s):

Absorption Spectra ◽

Near Infrared ◽

Peak Height ◽

Second Derivative ◽

Absorption Bands ◽

Derivative Spectra ◽

Nir Absorption ◽

Second Derivative Spectra ◽

Food Reserves ◽

Wheat Kernels

The near infrared (NIR) absorption spectra of deoxynivalenol (DON) and single wheat kernels with or without DON were examined. The NIR absorption spectra of 0.5–2000 ppm of DON in acetonitrile were recorded in the 350–2500 nm range. Second derivative processing of the NIR spectra and spectral subtractions showed DON absorption bands at 1408 nm, 1904 nm and 1919 nm. NIR spectra of sound and Fusarium-damaged kernels were also acquired using two instruments. Subtraction of average absorption spectra and second derivative spectra were evaluated to identify different NIR signatures of the two types of kernel. Differences in peak height and positions of the NIR absorption bands of the kernels were noted. At 1204 nm, 1365 nm and 1700 nm, the differences were in the heights of the absorption peaks. Such differences may be attributed to changes in the levels of grain food reserves such as starches, proteins and lipids and other structural compounds. Shifts in absorption peak positions between the two types of kernels were observed at 1425–1440 nm and 1915–1930 nm. These differences may arise from other NIR active compounds, such as DON, which are not common for the two types of kernel. Since the NIR absorption of DON may have contributed to the shifts between sound and Fusarium-damaged kernels, this study indicates the potential for NIR spectrometry to evaluate Fusarium damage in single kernels based on the DON levels.

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The role of dysprosium ions on the physical and optical properties of lithium-borosulfophosphate glasses

International Journal of Modern Physics B ◽

10.1142/s0217979217501016 ◽

2017 ◽

Vol 31 (13) ◽

pp. 1750101 ◽

Cited By ~ 11

Author(s):

Ibrahim Bulus ◽

S. A. Dalhatu ◽

R. Hussin ◽

W. N. Wan Shamsuri ◽

Y. A. Yamusa

Keyword(s):

Optical Properties ◽

Optical Absorption ◽

Absorption Spectra ◽

Physical Parameters ◽

Potential Candidate ◽

Optical Absorption Spectra ◽

Absorption Bands ◽

X Ray ◽

Nir Absorption ◽

Optical Applications

Achieving outstanding physical and optical properties of borosulfophosphate glasses via controlled doping of rare earth ions is the key issue in the fabrication of new and highly-efficient glass material for diverse optical applications. Thus, the effect of replacing P2O5 by Dy2O3 on the physical and optical properties of Dy[Formula: see text]-doped lithium-borosulfophosphate glasses with chemical composition of 15Li2O–30B2O3–15SO3–[Formula: see text]P2O5–[Formula: see text]Dy2O3 (where 0.0 mol.% [Formula: see text] mol.%) has been investigated. The glass samples were synthesized from high-purity raw materials via convectional melt-quenching technique and characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectrometry (EDX), density and UV–vis–NIR absorption measurements. The amorphous nature of the prepared glass samples was confirmed by XRD patterns whereas the EDX spectrum depicts elemental traces of O, C, B, S, P and Dy. The physical parameters such as density, refractive index, molar volume, polaron radius and field strength were found to vary nonlinearly with increasing Dy2O3 concentration. UV–vis–NIR absorption spectra revealed seven absorption bands with most dominant peak at 1269 nm (6H[Formula: see text]F[Formula: see text]H[Formula: see text]). From the optical absorption spectra, the optical bandgap and Urbach’s energy have been determined and are related with the structural changes occurring in these glasses with increase in Dy2O3 content. Meanwhile, the bonding parameters ([Formula: see text]) evaluated from the optical absorption spectra were found to be ionic in nature. The superior features exhibited by the current glasses nominate them as potential candidate for nonlinear optical applications.

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