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Raman spectroscopy has been used as a local probe to characterize the structural evolution of magnetron-sputtered decorative zirconium oxynitride ZrOxNy films which result from an increase of reactive gas flow in the deposition The lines shapes, the frequency position and widths of the Raman bands show a systematic change as a function of the reactive gas flow (a mixture of both oxygen and nitrogen). The as-deposited zirconium nitride film presents a Raman spectrum with the typical broadened bands, due to the disorder induced by N vacancies. The recorded Raman spectrum of the zirconium oxide film is typical of the monoclinic phase of ZrO2, which is shown also by X-ray diffraction. Raman spectra of zirconium oxynitride thin films present changes, which are found to be closely related with the oxygen content in films and the subsequent structural changes. ; FCT institution by the project nº POCTI/CTM/38086/2001 co-financed by European community fund FEDER ; European Union through the NMP3-CT-2003 505948 project ...

[EN] The structure of xBaO·(1 − x) PO (x = 0.30, 0.35, 0.40, 0.45, and 0.50) glasses was studied by Raman spectroscopy and thermodynamic model Shakhmatkin and Vedishcheva (SVTDM). The seven system components (defined as stable crystalline phases of the BaO–PO binary phase diagram) were considered in the SVTDM: BaO, PO, 4BaO·PO (B4P), 3BaO·PO (B3P), 2BaO·PO (B2P), BaO·PO (BP), and BaO·2 PO (BP2). Only the equilibrium molar abundances of BP and BP2 were non-negligible in all studied glass compositions. Therefore, in the next step, multivariate curve analysis (MCR) of the baseline—subtracted, thermally—corrected experimental Raman spectra, was performed for two components (BP2 and BP). MCR resulted in the Raman spectra (loadings) and relative abundances (scores) of each considered component. The MCR method reproduced 98.93% of the spectral data variance. Then, the decomposition of Malfait was used. The perfect fit between the MCR loadings and the partial Raman spectra of BP2 and BP, obtained by Malfait's decomposition, was found, confirming the validity of thermodynamic model. ; This paper is created in the frame of the Project FunGlass that has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 739566. This work was supported by The Slovak Grant Agency for Science under Grant No. VEGA 1/0064/18, and the Project Centre for Functional and Surface Functionalized Glass (CEGLASS), ITMS code is 313011R453, operational program Research and innovation, co-funded from European Regional Development Fund.

The paper presents the infrared and Laser Raman spectra of Samarium Chloride from 200-2000 cm-1 and 20-2000 cm-1 respectively. The vibrational analysis has been made for the samarium chloride on the basis of pyramidal C3v symmetry and the molecular constants are reported. The fundamental frequency of SmCl3 are A1 = 371, 84 cm-1 ; E = 510, 94 cm-1. The thermodynamic properties are also presented on the temperature range 298.16 K to 1300 K.

EUROfusion Enabling Research Project, Grant/Award Number: ENR‐MFE19.ISSP‐UL‐02; GENCI, Grant/Award Number: 2018‐[A0050810537] (Ph. D'Arco) Access to the HPC resources of CINES/IDRIS/TGCC obtained thanks to the grant 2018-[A0050810537] ; The infrared (IR) and Raman spectra of eight substitutional carbon defects in silicon are computed at the quantum mechanical level by using a periodic supercell approach based on hybrid functionals, an all electron Gaussian type basis set and the CRYSTAL code. The single substitutional C s case and its combination with a vacancy (C sV and C sSiV) are considered first. The progressive saturation of the four bonds of a Si atom with C is then examined. The last set of defects consists of a chain of adjacent carbon atoms Curn:x-wiley:01928651:media:jcc26206:jcc26206-math-0001, with i = 1–3. The simple substitutional case, C s, is the common first member of the three sets. All these defects show important, very characteristic features in their IR spectrum. One or two C related peaks dominate the spectra: at 596 cm−1 for C s (and C sSiV, the second neighbor vacancy is not shifting the C s peak), at 705 and 716 cm−1 for C sV, at 537 cm−1 for Curn:x-wiley:01928651:media:jcc26206:jcc26206-math-0002 and Curn:x-wiley:01928651:media:jcc26206:jcc26206-math-0003 (with additional peaks at 522, 655 and 689 for the latter only), at 607 and 624 cm−1, 601 and 643 cm−1, and 629 cm−1 for SiCurn:x-wiley:01928651:media:jcc26206:jcc26206-math-0004, SiCurn:x-wiley:01928651:media:jcc26206:jcc26206-math-0005, and SiCurn:x-wiley:01928651:media:jcc26206:jcc26206-math-0006, respectively. Comparison with experiment allows to attribute many observed peaks to one of the C substitutional defects. Observed peaks above 720 cm−1 must be attributed to interstitial C or more complicated defects. ; EUROfusion Enabling Research Project, Grant/Award Number: ENR‐MFE19.ISSP‐UL‐02; GENCI 2018‐[A0050810537]; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²

WOS: 000302285700022 ; The longitudinal optical (LO) phonon energy in AlGaN/GaN heterostructures is determined from temperature-dependent Hall effect measurements and also from Infrared (IR) spectroscopy and Raman spectroscopy. The Hall effect measurements on AlGaN/GaN heterostructures grown by MOCVD have been carried out as a function of temperature in the range 1.8-275 K at a fixed magnetic field. The IR and Raman spectroscopy measurements have been carried out at room temperature. The experimental data for the temperature dependence of the Hall mobility were compared with the calculated electron mobility. In the calculations of electron mobility, polar optical phonon scattering, ionized impurity scattering, background impurity scattering, interface roughness, piezoelectric scattering, acoustic phonon scattering and dislocation scattering were taken into account at all temperatures. The result is that at low temperatures interface roughness scattering is the dominant scattering mechanism and at high temperatures polar optical phonon scattering is dominant. ; European Union [PHOME, ECONAM, N4E]; TUBITAK [110T377, 109E301, 107A004, 107A012]; DPT; Anadolu University [BAP-1001F99]; Turkish Academy of Sciences ; This work is supported by the European Union under projects PHOME, ECONAM, N4E, and TUBITAK under Project Nos., 110T377, 109E301, 107A004, 107A012, and DPT under the project DPT-HAMIT, and Anadolu University under the project BAP-1001F99. One of the authors (E.O.) also acknowledges partial support from the Turkish Academy of Sciences. We would like to acknowledge Tulay TIRAS for the Raman spectroscopy measurements.

none ; 4 ; Authors: Almaviva S., Botti S., Palucci A., Puiu A., Schnurer F., Schweikert W., Romolo F.S. ; We report the results of Raman measurements on some common military explosives and explosives precursors deposited on clothing fabrics, both synthetic and natural, in concentration comparable to those obtained from a single fingerprint or mixed with similar harmless substances to detect illegal compounds for smuggling activities. Raman spectra were obtained using an integrated portable Raman system equipped with an optical microscope and a 785-nm laser in an analysis of <1 min. The spectral features of each illicit substance have been identified and distinguished from those belonging to the substrate fabric or from the interfering compound. Our results show that the application of Raman spectroscopy (RS) with a microscope-based portable apparatus can provide interpretable Raman spectra for a fast, in-situ analysis, directly from explosive particles of some ?m3, despite the contribution of the substrate, leaving the sample completely unaltered for further, more specific, and propedeutic laboratory analysis. We also show how the RS is suitable for detecting illegal compounds mixed with harmless substances for smuggling purposes or for counterfeiting activities. � 2014 Society of Photo-Optical Instrumentation Engineers. ; none ; 10840/6335 ; Puiu, A.; Palucci, A.; Botti, S.; Almaviva, S. ; Puiu, A.; Palucci, A.; Botti, S.; Almaviva, S.

Digital technology for quality control of field demulsifiers based on a numerical algorithm for processing digitized Raman spectra (RS) and infrared (IR) spectra was developed and tested. The width of the acceptance limit of the numerical criterion for deciding on the proper quality of demulsifiers for various values of the specific risk of making a false negative decision was calculated. IR and Raman spectra of active substances (Laprols, Neonols, Amines) used for the production of commercial demulsifiers have been registered. Spectral zones and characteristic lines of absorption (IR spectra) and emission (Raman spectra) specific for Laprols, Neonols, Amines have been determined. Using the characteristic spectral bands of the active ingredients, the compositions of demulsifier samples from different batches were compared.

The vibrational features of eight interstitial nitrogen related defects in silicon have been investigated at the first principles quantum mechanical level by using a periodic supercell approach, a hybrid functionals, an all electron Gaussian type basis set and the Crystal code. The list includes defects that will be indicated as Ni (one N atom forming a bridge between two Si atoms), Ni-Ns (one interstitial and one substitutional N atom linked to the same Si atom), Ni-Ni (two Ni defects linked to the same couple of silicon atoms) and Ni-Sii-Ni (two Ni defects linked to the same interstitial silicon atom). Four 〈0 0 1〉 split interstitial (dumbbell) defects have also been considered, in which one lattice atom splits in two, and as a result the two interstitial atoms are three fold coordinated: they are two N (indicated as IN-N), one N and one Si (IN-Si), one N and one C (IC-N). For comparison, also the case with two Si atoms (ISi-Si) has been included. Four of these eight defects have unpaired electrons, and have been described through the UHF (Unrestricted Hartree-Fock like) computational scheme. The local defect geometry and the charge and spin density distributions have been analyzed. For the first time, intensities of IR and Raman spectra were calculated along with the frequencies, and this is crucial for the comparison of theoretical simulations with experiments. All these defects present very characteristic features in their IR spectrum, dominated by one or two very intense peaks. It has been possible to find a simulated counterpart to each one of the five peaks reported by Stein in 1985 (Applied Physics Letters, 47, 1339), and then to establish a correspondence between the microscopic structure of the defects and the IR intense peaks. The Raman spectra are in all cases dominated by the perfect silicon peak at about 530 cm−1, and are then not very useful for the characterization of the defects. ; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²

Raman spectroscopy is employed to characterize structural and phonon properties of GaP/GaNP core/shell nanowires (NWs) grown by molecular beam epitaxy on Si substrates. According to polarization-dependent measurements performed on single NWs, the dominant Raman modes associated with zone-center optical phonons obey selection rules in a zinc-blende lattice, confirming high crystalline quality of the NWs. Two additional modes at 360 and 397 cm(-1) that are specific to the NW architecture are also detected in resonant Raman spectra and are attributed to defect-activated scattering involving zone-edge transverse optical phonons and surface optical phonons, respectively. It is concluded that the formation of the involved defect states are mainly promoted during the NW growth with a high V/III ratio. ; Funding Agencies|Vetenskapsradet (Swedish Research Council) [621-2010-3815]; U.S. National Science Foundation [DMR-0907652, DMR-1106369]; Royal Government of Thailand Scholarship

High-pressure Raman scattering measurements have been carried out in ZnGa2Se4 for both tetragonal defect chalcopyrite and defect stannite structures. Experimental results have been compared with theoretical lattice dynamics ab initio calculations and confirm that both phases exhibit different Raman-active phonons with slightly different pressure dependence. A pressure-induced phase transition to a Raman-inactive phase occurs for both phases; however, the sample with defect chalcopyrite structure requires slightly higher pressures than the sample with defect stannite structure to fully transform into the Raman-inactive phase. On downstroke, the Raman-inactive phase transforms into a phase that could be attributed to a disordered zincblende structure for both original phases; however, the sample with original defect chalcopyrite structure compressed just above 20¿GPa, where the transformation to the Raman-inactive phase is not completed, returns on downstroke mainly to its original structure but shows a new peak that does not correspond to the defect chalcopyrite phase. The pressure dependence of the Raman spectra with this new peak and those of the disordered zincblende phase is also reported and discussed. © 2013 AIP Publishing LLC ; This study was supported by the Spanish government MEC under Grants No. MAT2010-21270-C04-01/03/04, by MALTA Consolider Ingenio 2010 project (CSD2007-00045), and by the Vicerrectorado de Investigacion y Desarrollo of the Universitat Politecnica de Valencia (UPV2011-0914 PAID-05-11 and UPV2011-0966 PAID-06-11). E.P.-G., A.M., and P.R.-H. acknowledge computing time provided by Red Espanola de Supercomputacion (RES) and MALTA-Cluster. ; Vilaplana Cerda, RI.; Gomis Hilario, O.; Pérez-González, E.; Ortiz, HM.; Manjón Herrera, FJ.; Rodríguez-Hernández, P.; Muñoz, A. (2013). High-pressure Raman scattering study of defect chalcopyrite and defect stannite ZnGa2Se4. Journal of Applied Physics. 113:2335011-23350110. https://doi.org/10.1063/1.4810854 ; S ; 2335011 ; 23350110 ; 113 ; A. ...