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This article presents the synthesis of Au/Li nanoparticles through green synthesis approximation, using extract from Opuntia ficus indica (OFI). The TEM images show the efficiency of this method for the synthesis of nanoparticles. The vibrational properties of Au/Li nanoparticles were analyzed through Raman spectroscopy. The results of the analysis show two vibrational bands around 93 cm−1and 242 cm−1. Furthermore, the article presents a theoretical study of clusters AumLikin which obtained minimum energy structures were obtained and predicted the normal modes of vibration in the Raman spectrum of each one of the clusters AumLik. We observed a theoretical and experimental behavior in the optical and the vibrational properties.

The 1+1 REMPI spectrum of SiO in the 210–220 nm range was recorded. Observed bands were mostly assigned to the vibrational bands v ″ = 0 - 3 , v ′ = 5 - 10 of the A - X electronic transition. Additionally, a band near 216–217 nm was tentatively assigned as a 2-photon transition from X to the n = 12 , 13 [ X 2 Σ + , v + = 1 ] Rydberg states. Based on observed lines we estimated the IP of SiO to be 11.594(5) eV. The SiO+ cation has previously been identified as having a cycling transition useful for state control by optical pumping. Our work allowed us to identify an efficient method for loading an ion trap with rotationally and vibrationally cold SiO+ from an ablated sample of SiO by photoionizing through the (5,0) A - X band at 213.977 nm.

We compare the intensities of purely rotational and ro-vibrational transitions within the ground electronic state of CO calculated with two dipole moment functions (DMFs) of Li et al. (2015) and four potential energy functions (PEFs), a semi-empirical PEF of Meshkov et al. (doi: https://doi.org//10.5281/zenodo.1198744) and three empirical ones due to Coxon and Hajigeorgiou (2004, 2016, 2017). All these PEFs reproduce the experimental line positions with similar normalized standard deviations (NSDs), and the energy mismatch between the vibrational levels with v ⩽ 5 does not exceed 0.0002 cm−1 among all PEFs. Despite these similarities, we find that the rotational anomalies in the 0-0, 1-1, 2-2, 3-3, 4-4, and 5-0 bands shown in Figs. 3 and 4 of Medvedev et al. (2017) change their intensities by a factor of 2 to 250 among the above PEFs at a given DMF. Both the positions and intensities of the anomalies change between two DMFs at a given PEF.

Unintentionally doped cubic boron nitride (cBN) single crystals with color zoning were investigated by Raman spectroscopy. Besides the TO mode at 1053 cm−1 and the LO mode at 1304 cm−1, some little vibrational bands at 925 cm−1, 955 cm−1and 1247 cm−1 corresponding to the amber regions in the { 1 ¯ 1 ¯ 1 ¯ } N sectors of cBN crystals were observed. These vibrational bands probably result from the disorder-activated Raman scattering (DARS) due to the high defect densities. It is shown that these defects and impurities are nonuniform, easily formed and incorporated in { 1 ¯ 1 ¯ 1 ¯ } N growth sectors during the growth process of cBN crystals. These defects and impurities are color centers in cBN, therefore, the cBN crystal exhibits symmetrical color zoning relative to the {111} growth sectors.

In this study, a surface-enhanced Raman scattering (SERS) spectroscopic approach was developed for a trace-level detection of procainamide in an aqueous medium. Silver-based nanoparticles as active substrates were synthesized using the reduction technique in presence of a citrate stabilizer and were characterized with UV–Vis, FT-IR, and FE-SEM techniques. The SERS spectra of procainamide were collected at a wide concentration range. The vibrational bands and frequency shifts associated with the enhanced Raman signals were identified, analyzed, and assigned to respective active modes. First-principle calculations were performed to elaborate on potential substrate-drug interaction possibilities and energies at the molecular level. The intensity enhancements observed for selected SERS peaks, namely at 1246 cm−1, 1370 cm−1, 1613 cm−1 and 1661 cm−1, were further utilized for the development of a consistent and fast quantification of procainamide. The developed approach displayed an excellent sensitivity and good reproducibility. The detection limit for procainamide was successfully attained at the level of one-tenth of nanomolar concentrations corresponding to a coefficient of regression (R2) of 0.9998. The obtained results revealed that this method is promising for drug and medical applications.

From γ-γ-γ and γ-γ-γ-γ coincidence studies of spontaneous fission of 252Cf, new high spin states in 148Ce were identified. The octupole bands with s = + 1 and s = − 1 are expanded with spins with 28+ and 18−, respectively. Importantly, a 1γ vibrational band has been established up to 14+ and a 1β vibrational band up to 6+. The levels in γ and β bands in 148Ce are compared systematically to those in neighboring 150Nd and 152Sm isotones. This comparison informs the role of deformation and shape transition in this mass region. New 3− and 5− members of the s = + 1 octupole band were observed.

In this work, a full factorial design 23 for the optimization of experiments was performed using a portable Raman spectrometer to find ideal instrumental conditions (laser power, analysis accessory, and luminosity) in the detection and quantification of adulterant, soybean oil, in extra virgin olive oil (EVOO). The ratio between the intensities of vibrational bands of 1440 and 1266 cm–1, characteristics of oleic and linoleic acids, respectively, were evaluated as a response measure. It was found that the configuration of the accessories has no significant influence on the analytical response. For quantification of soybean oil in EVOO, an analytical curve was constructed with six concentrations of the binary mixture containing EVOO with soybean oil (100/0; 80/20; 60/40; 40/60; 20/80; and 0/100 % v/v) and the model was validated from use of five samples adulterated with known concentrations (90/10; 70/30; 50/50; 30/70; and 10/90 % v/v) employing the intensity (I) ratio of the I1266/I1440 and I1656/I1440. The best regression method, using ordinary least squares (OLS), was through the ratio of the intensity of I1266/I1440, which presented higher linearity with R2c and R²p of 0.9769 and 0.9450, respectively; and Root Mean Square Error of Calibration (RMSEC) and Root Mean Square Error of Prediction (RMSEP) of 1.445 and 1.975 % (v/v), respectively.

The present work reports the detailed molecular, structural and spectral studies including DFT, FTIR, FT-Raman, NMR, UV Vis. spectrum of a bimetallic salt, [Ni(L)][CoCl 4 ] where L = 3,7- bis (2-aminoethyl)-1,3,5,7-tetraazabicyclo(3.3.1)nonane using DFT/TD-DFT calculations, FTIR, FT-Raman, NMR and UV Vis. spectra. The bimetallic salt, [Ni(L)][CoCl 4 ] was found to crystallize in the space group P1 with unit cell dimensions a = 7.1740(15), b = 8.1583(16) and c = 8.3102(16) A as reported elsewhere. The molecular structure, IR and NMR ( 13 C and 1 H) spectra of the bimetallic salt were interpreted by comparing the experimental results with the theoretical one using B3LYP/6–31G(d,p) calculations. The vibrational bands appearing in the FTIR and FT-Raman are assigned using animated modes. Molecular properties like HOMO–LUMO analysis, non-linear optical properties, atomic charges and thermodynamic properties have also been studied at the same level of theory. The theoretical results are found in good correlation with the experimental data. Moreover, the Hirshfeld analysis was carried out to ascertain the secondary interactions and associated 2D fingerprint plots.

Analysis of the continuum absorption in water vapor at room temperature within the purely rotational and fundamental ro-vibrational bands shows that a significant part (up to a half) of the observed absorption cannot be explained within the framework of the existing concepts of the continuum. Neither of the two most prominent mechanisms of continuum originating, namely, the far wings of monomer lines and the dimers, cannot reproduce the currently available experimental data adequately. We propose a new approach to developing a physically based model of the continuum. It is demonstrated that water dimers and wings of monomer lines may contribute equally to the continuum within the bands, and their contribution should be taken into account in the continuum model. We propose a physical mechanism giving missing justification for the super-Lorentzian behavior of the intermediate line wing. The qualitative validation of the proposed approach is given on the basis of a simple empirical model. The obtained results are directly indicative of the necessity to reconsider the existing line wing theory and can guide this consideration.

An ethyl-substituted diamidine, 1,8-bis(N,N'-diethylamidino)anthracene (1), for the recognition of dicarboxylic acids has been designed and synthesized. The complexation of diamidine 1 with dicarboxylic acids 3, 4 and α,ω−dicarboxylic acids 6 (C6-C11), showed the formation of 1:1 complexes in CH3CN. On the other hand, for the complexation with a monocarboxylic acid and α,ω−dicarboxylic acids 6 (C3-C5), formation of the amidinium 1·2H+ was observed. The crystal structures of the 1:1 complexes of the diamidine 1 and the α,ω−dicarboxylic acids 6 were obtained, and an unusual “U-shaped conformation” of 6 was observed. Furthermore, fluorescence spectra of the diamidine 1 showed “structural vibrational bands” derived from the anthracene unit after recognition of the α,ω−dicarboxylic acids (C6-C11). However, for the formation of the dissociated amidinium 1·2H+, broad fluorescence bands were observed (without a vibrational structure). Consequently, the stability of the formed complexes can be analyzed by the patterns (vibrational structures) of the fluorescence spectra.

An analysis of the measured He-, Ar- and Kr- broadening coefficients γ for 1575 water vapor transitions of 27 vibrational bands belonging to the 0.6–11,200 cm−1 spectral region is performed using an empirical function that contains adjustable parameters. A universal function is detected during the analysis. This function depends on the parameters that are common for all perturbers A = (He, Ar or Kr). A universal function multiplied by one additional parameter x20(A) determines the broadening coefficients γ(A) for each perturber A = (He, Ar or Kr).Two fitting procedures are used. The first considers the fit of measured γ(exp) for individual rotational branches while the other considers the global fit of all 1575 measured γ(exp). In the second procedure, ratios of γ(Kr)/γ(He) = 2.543 ± 0.040 and γ(Kr)/γ(Ar) = 1.252 ± 0.036 are found. The coefficients derived from the fitted parameters are compared statistically to measured coefficients.

This work deals with the successful synthesis, spectroscopic properties (Raman and infrared) and theoretical calculations of some quinoline derivatives, namely 4-azido-7-chloroquinoline and the commercially available 4,7-dichloroquinoline, quinolin-8-ol. The analysis of the Raman and infrared spectra of the quinoline derivatives, supported by DFT calculations, for the first time has afforded the opportunity to characterize unambiguously the main vibrational bands for these important molecules, which are mainly used as anti-malaria compounds. Despite the very similar structures of these quinolines the Raman and infrared spectra exhibit significant wavenumber shifts for several key bands. A characteristic band at ca. 1580 cm −1 can be assigned involving a δ(OH) mode for quinolin-8-ol (QNO) as well as the band at ca. 1090 cm −1 attributed to δ(CCl) for 4,7-dichloroquinoline (DCQN). The compound 4-azido-7-chloroquinoline (ACQN) shows a very characteristic marker band at ca. 1300 cm −1 , which has been assigned to the ν(NN) mode of the azide group.

Self- and N2-broadening coefficients have been retrieved for 566 lines of C2H4 at room temperature in the 5 μm region including the ν7 + ν8, ν4 + ν8, ν6 + ν10, ν6 + ν7, ν4 + ν6 and ν3 + ν10 vibrational bands. Measurements have been performed using Fourier transform infrared spectroscopy. The lines were fitted with a single-spectrum non-linear least squares fitting procedure of Voigt profiles which appeared to properly model the observed molecular line shapes within the noise level. The experimental results are compared with theoretical values calculated using the Robert and Bonamy formalism which reproduces the measured broadening coefficients. For the self- and N2-broadening coefficients, the average discrepancy 〈(γmea − γcal/γmea) × 100〉 for 566 lines, is (−1.6 ± 7.8)% and (−2.8 ± 9.9)%, respectively. One standard deviation is given after ±. These coefficients show dependence with both rotational quantum numbers J and Ka. Comparisons with previous measurements taken in the ν7 band of C2H4 show difference range between 7% and 15%. These differences not insignificant can come from inconsistency between experimental measurements.

The FTIR and FT-Raman spectra of anilazine have been recorded in the range 400–4000 cm−1 and 50–3500 cm−1 respectively. The optimized geometrical parameters of the compound were calculated using B3LYP method with 6-311G(d,p) basis set. The distribution of the vibrational bands were carried out with the help of normal coordinate analysis (NCA). The 1H and 13C nuclear spectra have been recorded and chemical shifts of the molecule were also calculated using the gauge independent atomic orbital (GIAO) method. The UV–Visible spectrum of the compound was recorded in the region 190–900 nm and the electronic properties were determined by time-dependent DFT (TD-DFT) approach. Anilazine was screened for its antifungal activity. Molecular docking studies are conducted to predict its fungicidal activity.

To demonstrate the validity of o -carborane as an electronic anchoring unit for constructing robust conjugation system, bi(benzo[ b ]thiophene)-fused o -carborane was designed and synthesized. From the optical measurements, clear vibrational bands not only in the absorption but also in the emission spectra were observed. These data mean that the electronic delocalization should occur on the rigid template. In the cyclic voltammograms, the reversible reduction waves at −1.72 eV and −2.37 eV were detected that originated from the electron-accepting ability of o -carborane. It is suggested that o -carborane should be the versatile unit for constructing robust conjugation with electron-accepting ability.

The water vapor line broadening γ and shift δ coefficients in the ν 1 + ν 2 , ν 2 + ν 3 , ν 1 + ν 3 , 2ν 3 , 2ν 1 , 2ν 2 + ν 3 , and ν 1 + 2ν 2 vibrational bands were obtained from the analysis of the H 2 O–He absorption spectra, recorded in the region from 5000 to 7500 cm −1 with the spectral resolution of 0.01 cm −1 using a Bruker IFS 125HR FTIR spectrometer. The vibrational bands 2ν 3 and ν 1 + 2ν 2 were investigated for the first time. The calculations of γ and δ were performed in the framework of the semi-classical method. The rotational contributions as well as the contributions connected with the accidental resonances were taken into account in the used H 2 O–He interaction potential. The analytical representation of the broadening coefficients γ at planetary temperatures was introduced and discussed.

Effect of solvation on coumarin6 dye has been studied with density functional theory (DFT). Optimized structure of the dye has been obtained in various solvents and frequencies of various vibrational bands have been calculated in these solvents. Calculations predict shift in the frequency of certain bands in the solvents. Similar shifts have been observed experimentally in the vibrational spectra of the dye in solvents. In order to ascertain the origin of these shifts, the interactions of solvent molecules with the coumarin6 molecule have been studied using various tools of DFT like donor-acceptor interactions, Molecular Electrostatic potential (MEP) and HOMO-LUMO analysis etc.

We report rotational profiles in the laser induced fluorescence excitation spectrum recorded for the B 3 1(5 3 P 1 ) ⿿ X 1 0 + (5 1 S 0 ) transition in CdNe van der Waals complex. A method of analyzing the rotational structure of overlapping vibrational bands with isotopic spectral contributions is discussed. Rotational characteristics B Ͽ and D Ͽ for the Ͽ⿲ = 0, 1, 2 and Ͽ⿳ = 0 are reported.

The semiclassical formalism of Robert and Bonamy is used to calculate the linewidths of rovibrational transitions of ammonia in collision with argon. Two accurate ab initio potential energy surfaces (PES) have been applied to model the NH3-Ar interactions. In this work and contrary to our previous calculations, the transitions with ΔK = ±3n (n integer) have been introduced into the expressions of the differential collision cross section S(b). Comparisons with previous theoretical and experimental studies are reported. A detailed analysis of the contribution of the various anisotropic components of the PES shows that the induced ΔK = ±3 transitions play a crucial role. Calculations performed in the ν4 and ν1 vibrational bands of NH3 are in good agreement with the experimental data and correct dependences of the broadening coefficients with the rotational quantum numbers J and K are obtained., SCOPUS: ar.j, info:eu-repo/semantics/published

Because of high temperature, the experimental diagnosis for the combustion intermediates of hydrocarbon fuel is still a great challenge. In this letter, we propose a method to detect qualitatively the combustion intermediates by introducing temperature into the expression of vibrationally resolved electronic spectrum, which is based on the relationship between molecular structure and its spectrum. Using this method, the fine electronic spectra of CO+ and N2+ molecules are simulated, and the results reproduce their experimental ones very well, indicating the reliability of this method. Further, the electronic spectra of combustion intermediates C2N, NO2, OOH and HCO are predicted and the main vibrational bands are assigned. This work provides theoretical guidance for the qualitative detection of hydrocarbon fuel combustion intermediates under high temperature.

FTIR spectra of the 2-0 band of HCl have been measured in the 5300–5900 cm−1 spectral region at 15 different pressures (0.05–2.5 bar) and at a spectral resolution of 0.07 cm−1. For the first time, reliable and consistent self-induced broadening and shift coefficients for the complete HCl 2-0 band have been reported. Line intensities determined from a robust regression analysis with improved uncertainties are also presented. Compared to previous laser-based measurement for the R3 line {Ortwein et al., Appl Phys B: Lasers Opt 2010;100:341–7}, our newly measured γ s e l f coefficient and line intensity are 1.35% and 0.10% larger, respectively. Hartmann and Boulet {Hartmann & Boulet, JCP 113, 9000 (2000)} developed a formalism describing the relation between the shift coefficients of different vibrational bands and successfully applied to Ar–HF system. Our newly measured self-induced shift coefficients suggest that the H–B formalism is not suitable for describing the HCl–HCl collisional system.

The DFT (B3LYP) calculations on a synthetic steroidal molecule 7a-Aza-B-homostigmast-5-eno [7a,7-d] tetrazole, C 29 H 48 N 4 , have been performed. The molecular structure, IR and NMR ( 13 C and 1 H) spectra of the present compound were interpreted using experiments (XRD, FTIR, NMR) as well as theoretical, B3LYP/6-311 + G(2d,p), calculations. The vibrational bands appearing in FTIR are assigned with great accuracy using animated modes. Molecular properties like HOMO–LUMO analysis, chemical reactivity descriptors, MEP mapping, dipole moment and Mullikan's atomic charges have been presented at the same level of theory. The theoretical results are found in good correlation with experimental data. Moreover, the Hirshfeld analysis was carried out to ascertain the secondary interactions and associated 2D fingerprint plots. The in vivo cytotoxicity of 7a-Aza-B-homostigmast-5-eno [7a,7-d] has also been carried out against brine shrimp nauplii by lethality bioassay.

The vibration–rotational structure of the ground A2′ state of the NO3 radical is re-considered, because Hirota (2015) presented an objection to the vibrational assignment of our previous papers (Kawaguchi et al., 2011, 2013; Fujimori et al., 2013). The present study examines the vibrational assignment in the following points, (1) laser induced fluorescence (LIF) spectra observed by Fukushima and Ishiwata in the 1050 cm−1 region, (2) Fourier transform (FT) spectra of vibrational bands from the v4 = 1 state, and a diode laser spectrum of the 2ν4 band. These considerations support our previous assignments, that is, ν3 + ν4 = 1492 cm−1 and ν3 = 1055 cm−1 for 14NO3.

This paper reports an experimental study about the pressure dependence of the vibrational modes of tricosane paraffin (C 23 H 48 ) investigated by in situ Raman and infrared spectroscopy in a diamond anvil cell (DAC). The main vibrational bands were followed up to 11 GPa and the observed behavior indicated a conformational disorder induced by pressure, corresponding to a transition from ordered to disordered state of the linear chains from 2 to 5 GPa followed by a transition to an amorphous state under pressure above 5 GPa. However, this behavior was reversible after compression–decompression cycle showing that this linear compound was structurally and chemically stable up to 11 GPa at room temperature.

Linestrengths, N 2 -, Ar-, He- and self-broadening coefficients of acetylene have been measured at 296 K in the P branch of the ν 4 +ν 5 combination band for 25 rotational transitions. The effect of gas temperature is studied over 296–683 K for five transitions to allow the determination of the temperature dependent exponent n for N 2 - and Ar-broadening coefficients. These measurements were performed using a continuous-wave quantum cascade laser (cw-QCL) operating over 1253–1310 cm −1 . Spectroscopic parameters were obtained by fitting absorption spectra using Voigt, Galatry and Rautian profiles. Linestrength and broadening results are compared with previous studies available in literature for the ν 4 +ν 5 combination band and other vibrational bands of acetylene.

The vibrational structure of silica-supported vanadium oxide species has been studied by normal mode analysis using polyhedral oligomeric silsesquioxanes (POSSs) to describe the silica support. The analysis reveals that the vanadium oxide-related vibrational bands are characterized by significant contributions of several force constants. Their discussion in terms of single bond-unit designators is therefore not adequate. The consideration of the silica support is shown to be of importance for the vibrational spectrum. The theoretical results are fully consistent with experimental data for a silica-supported vanadium oxide catalyst with a vanadium coverage of 0.7 atoms/nm 2 .

Analysis of profiles of ( υ ′; υ ″ = 0) vibrational bands, ( υ ′ = 0,1,2,4,5), recorded with partly resolved rotational structure using the B 3 1(5 3 P 1 ) ← X 1 0 + (5 1 S 0 ) transition in CdAr is presented. The analysis allowed for determination of the B v ′ and D v ′ rotational constants, and new values of ω e ′ vibrational frequency and D e ′ well depth of the B 3 1-state interatomic potential. The new characterization of the B 3 1 state in CdAr is closer to the result of recent ab initio calculations [Chem. Phys. Lett. 471 (2009) 29] than results of our previous study performed with vibrational resolution [Spectrochim. Acta A 56 (2000) 1613].

The infrared spectra of SiD4 isotopologues with the abundances of 92.23 % for 28SiD4, 4.68 % for 29SiD4, and 3.09 % for 30SiD4 were measured in the region of 3020–3260 cm − 1 with a Bruker IFS 120HR Fourier transform spectrometer and analysed. For 28SiD4 1473 transitions with Jmax = 36 were assigned to the tetradecad stretching bands ν 1 + ν 3 ( F 2 ) , 2ν3(F2) and 2ν3(E). Rotational, centrifugal distortion, tetrahedral splitting, and interaction parameters were determined from the fit of experimental line positions. A set of 31 parameters, obtained from the fit, reproduces the initial experimental data with the d rms = 3.5 × 10 − 4 cm − 1 which is close to experimental uncertainty. The results of the analogous analyses for the ν 1 + ν 3 band of the 29SiD4 and 30SiD4 isotopologues are also presented with 199 and 169 assigned transitions. A list of experimental transitions is presented as a Supplementary material part.

High-resolution infrared spectra of the ν 12 + ν 6 − ν 6 (around 820 cm−1) and ν 11 − ν 12 (around 370 cm−1) bands of 12CH313CH3 were measured. Frequencies from these bands together with data from the ν 12 and ν 5 fundamentals and the torsional bands were analyzed in a 4-state fit to determine the torsion mediated Coriolis and Fermi interactions. As compared to normal ethane this lower symmetry isotopologue shows more complicated vibrational couplings. The combined data set includes more than 6800 frequencies and was fitted to within experimental accuracy using a 78-parameter Hamiltonian. The first determination of molecular parameters for the ν11 state of 12CH313CH3 has been made and using this Hamiltonian we provide lower state energies and partition functions between 100 and 320 K in increment of 10 K for planetary data analysis.

Absolute individual line intensities of numerous transitions of the fundamental ν 2 and ν 10 bands of oxirane (ethylene oxide, cyc-C 2 H 4 O) have been measured in the 1420–1560 cm −1 region using seven high-resolution Fourier transform spectra recorded at 0.002 cm −1 resolution and various pressures. These line intensities were least-squares fit using a theoretical model which takes into account the vibration–rotation interactions linking the upper state rotational levels, and, therefore, accurate rotational expansion of the transition moments of the ν 2 and ν 10 vibrational bands were derived. Using the coefficients obtained in the fitting, a line list of both bands has been generated. Comparisons with measurements taken at low resolution of the ν 2 / ν 10 dyad system show excellent agreement.

We report here the results of high accurate, ( 1 − 2 ) × 10 − 4 cm − 1 , ro-vibrational analysis of the ethylene molecule in the region of 640–1535 cm−1. More than 1110, 5060, 4670, and 2900 transitions belonging to the ν 4 , ν 7 , ν 10 , and ν 12 bands were assigned in the experimental spectrum with the maximum values of quantum numbers J max . / K a max . , equal to 36/11, 50/21, 40/17 and 48/17, respectively. Rotational and centrifugal distortion parameters of the ground vibrational state were improved on the basis of assigned transitions and high accurate saturated absorption experimental data known from the literature. The inverse spectroscopic problem was solved for the set of strongly interacting ( v 4 = 1 ) / ( v 7 = 1 ) / ( v 10 = 1 ) / ( v 12 = 1 ) states. The set of 78 parameters obtained from the fit reproduces values of 3644 initial “experimental” ro-vibrational energy levels (more than 13,740 assigned transitions of the ν 4 , ν 7 , ν 10 , and ν 12 bands) with the rms=0.00023 cm−1. In this case, the 197 high accurate saturated absorption transitions are reproduced with the rms=18.5 kHz.

The possibilities of using infrared and Raman microspectroscopic techniques for identification of selected red dyes contained in the colour layers of oil paintings were studied and critically discussed. The samples involved aged and non-aged model materials, containing kamala, logwood, cochineal, madder and lac dyes. The specific spectral bands found for the dyes were compared with the vibrational bands of their principal colouring components. The results indicate that IR microspectroscopy permits the identification of lac (the bands at 1715, 1378 and 1309 cm −1 ), kamala (the bands at 1551, 1346, 1167 and 1130 cm −1 ), and logwood (the bands at 1503, 1476, 1293, 1209 and 1056 cm −1 ), even in the spectra of aged model samples. The characteristic vibrational bands of the principal colouring components of madder and cochineal are hidden under the matrices of these dyes. The Raman microspectroscopy only permits reliable identification of kamala (the bands at 1625, 1600, 1550 and 998 cm −1 ) and logwood (the bands at 1607, 1565, 1414, 1394 and 701 cm −1 ). Both the microspectroscopic methods are suitable for identification of kamala in model samples of colour layers containing inorganic whites.

For substances 4-( n -hexyloxy)phenyl-4′-( n -octyloxy)benzoate and 4-( n -octyloxy)phenyl-4′-( n -hexyloxy)benzoate forming liquid–crystalline mesophases the Raman spectra in the region of 1000–3000 cm −1 were measured and assigned. The information on molecular geometry was obtained by quantum-chemical simulation. The calculations were made using the Gaussian-03 package at the HF/3-21G level of theory. Separately we investigated the temperature dependence of Raman spectra for the vibrational bands in the spectral range 1100–1350 and 1550–1750 cm −1 during the cooling process. The cooling rate was 1–2 K/min, and quasi-static condition of appropriate temperature processes was achieved in such a way. Noticeable changes in Raman spectra with temperature changing indicating the phase transitions are reported.

We have investigated the Raman spectra of different regioisomeric forms of monoacyl and diacyl chlorogenic acids. Raman spectra of 3-caffeoylquinic acid, 4-caffeoylquinic acid, 5-caffeoylquinic, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, and a synthetic derivative of 3-feruloylqunic acid were recorded using visible Raman spectroscopic technique and vibrational bands are assigned. Additionally, a theoretical study of 5-caffeoylquinic acid was performed using Gaussian 03. (C) 2012 Elsevier B.V. All rights reserved.

The absorption spectrum of water vapor enriched by deuterium and oxygen-18 is analyzed in the 6000–9200 cm−1 region. The spectrum has been recorded at room temperature with a Bruker IFS 120 h Fourier transform spectrometer. More than 14,000 absorption lines were measured in the recorded spectrum. The vibration–rotation assignments were performed on the basis of previously published experimental energies and of variational calculations. Nine water species (H216O, HD16O, D216O, H218O, HD18O, D218O, H217O, HD17O and D217O) were found to contribute to the observed absorption. More than 3600 lines of 19 vibrational bands of D218O and about 4700 lines of 16 bands of HD18O with J as high as 19 and Ka as high as 11 were assigned. The main part of the HD18O and D218O lines and all lines of HD17O and D217O were observed in the laboratory for the first time. The obtained vibration–rotation energy levels are compared with previous experimental studies and the results of variational calculations.

Variational calculations of the vibrational terms G v and rotational constants B v of the 14 N 15 N 16 O, 15 N 14 N 16 O and 15 N 15 N 16 O isotopologues of nitrous oxide are carried out using normal hyperspherical coordinates. The Morse-cosine potential energy surface for N 2 O previously determined by the authors by fitting to a set of experimental vibrational frequencies is employed. The G v and B v spectroscopic constants calculated for the 15 N substituted isotopologues show an satisfactory agreement with those experimentally observed for a large number of vibrational bands of these isotopologues recently measured. Predicted calculated values of these spectroscopic constants for unobserved vibrational bands of the 15 N substituted isotopologues are given in order to be of help in the identification and characterization of such bands, as a complement to the use of global effective Hamiltonians.

FT-IR and FT-Raman spectra of (E)-N-carbamimidoyl-4-((3,4-dimethoxybenzylidene) amino) benzenesulfonamide were recorded and analyzed. The vibrational wavenumbers were computed using HF/6-31G*, B3PW91/6-31G* and B3LYP/6-31G* basis. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands obtained experimentally. The results indicate that the B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and structural parameters. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The geometrical parameters of the title compound are in agreement with that of similar derivatives.

High resolution laser spectrum of scandium monoiodide (ScI) between 613 and 704 nm has been investigated using the technique of laser vaporization/reaction with free jet expansion and laser induced fluorescence spectroscopy. Seven vibrational bands of the D 1 Π–X 1 Σ + transition of ScI were recorded and analyzed. Accurate molecular constants for the v = 0–2 levels of the D 1 Π state and the v = 0–3 levels of the X 1 Σ + state were obtained. Detailed analysis of the recorded spectrum indicates that the v = 2 level of the X 1 Σ + state is perturbed by the v = 1 level of the a 3 Δ 1 state at J = 8. A comparison of molecular constants for the D 1 Π and X 1 Σ + states of scandium monohalides indicates a weakening of chemical bonding between the scandium and the halogen atoms down the group.

The infrared spectroscopic data for a series of three 2,3,9,10,16,17,23,24-octakis(hexylsulfonyl)phthalocyanine compounds with eight strong electron-withdrawing hexylsulfonyl groups at the peripheral positions M[Pc(SO 2 C 6 H 13 ) 8 ] [M = 2H ( 1 ), Cu ( 2 ), Zn ( 3 )] have been collected with resolution of 2 cm −1 . The infrared spectra of compounds 1 and 3 have also been calculated at the density functional B3LYP level. Detailed assignments of the vibrational bands in the IR spectra have been achieved through comparison of the experimental and calculated results. The influence of the metalation and the substitution of eight strong electron-withdrawing alkylsulfonyl groups on the IR characteristics of the phthalocyanines has been discussed based on the comparison between corresponding data.

Electronic structure calculations and spectroscopic assignments for metallophthalocyanines NiPc, PdPc and PtPc are performed on optimized geometries at B3LYP/LANL2DZ level. The order of the sizes of the central hole is computed to be PdPc > PtPc > NiPc, with the hole size of PdPc close to that of PtPc. The Mulliken charges of the central M vary in the order of PtPc > NiPc > PdPc, and the HOMO–LUMO gaps are in the order of NiPc NiPc > PdPc, which is the same order as experiment. Furthermore, the metal–ligand vibrational bands for Raman spectra shift in the order NiPc > PtPc > PdPc. The strongest Raman lines predicted at 1562, 1532 and 1534 cm−1 for NiPc, PdPc and PtPc are very sensitive to the metal ion.

Isotopic and rotational structures of the ( υ ′, υ ″) = (13,5), (14,5), (16,5) and ( υ ′, υ ″) = (0,1)–(6,1) vibrational bands of the E 3 Σ + ← A 3 Π 0 + and E 3 Σ + ← B 3 Σ 1 + transitions in CdAr, respectively, as well as the ( υ ′, υ ″) = (21,9) of the E 3 Σ + ← A 3 Π 0 + transition in CdKr were investigated using free-jet expansion beam and laser excitation. An optical–optical double resonance process was employed from the X 1 Σ 0 + + to the E 3 Σ + Rydberg via the A 3 Π 0 + or B 3 Σ 1 + intermediate electronic state. The structure of the bands with resolved isotopic structure was analyzed including their rotational structure. Analysis and simulation of the bands provided values for vibrational and rotational characteristics of the states. The analysis extended our previous low-resolution studies performed for the E 3 Σ + ← A 3 Π 0 + and E 3 Σ + ← B 3 Σ 1 + transitions.

Electronic transition spectrum of iridium monoboride in the spectral region between 400 and 545 nm has been recorded and analyzed using laser vaporization/reaction free jet expansion source and laser induced fluorescence spectroscopy. Thirteen vibrational bands belonging to four electronic transitions, namely the [18.8] 3 Δ 3 – X 3 Δ 3 , [21.1] 3 Φ 4 – X 3 Δ 3 , [22.8] 3 Φ 3 – X 3 Δ 3, and [22.4] 1 Φ 3 – a 1 Δ 2 transitions, have been identified and rotationally analyzed. Spectra of all four isotopic molecules were observed.

Relative intensities in the absorption spectrum of the B 1 Π u − X 1 Σ g + band system of diatomic silver are measured for the first time. Analysis of these measurements is performed using Rydberg–Klein–Rees potential curves derived from the best available vibrational and rotational constants for this band system. Comparison of measured and calculated absorption band strength ratios for eleven vibrational bands reveals that the relative electronic transition moment function (ETMF) of the Ag2 B−X system has a negative slope and decreases by ≈ 40 % over the 2.43–2.58 A range of internuclear distance. The ETMF shows some nonlinear structure; however, the empirical error bars suggest that a linear model is appropriate, thus allowing the r-centroid approximation as a simplification in our analysis.

The pressure-induced N 2 shift and broadening coefficients for nine lines of 12 C 2 H 2 in the ν 4 + ν 5 band located around 1330 cm − 1 were measured using a tunable diode-laser spectrometer coupled with a low temperature absorption cell. The measurement of these coefficients was realized at six temperatures (between 173.2 and 298.2 K) in order to determine their temperature dependence. The broadening coefficients were obtained by fitting the Voigt lineshape, and the Rautian and the Galatry models which take into account the collisional narrowing due to molecular confinement, to the experimental profile. The shift coefficients were determined using a procedure where calibration lines were simultaneously recorded with transitions from the gas sample under study. In order to detect a possible velocity effect of the C 2 H 2 − N 2 mixture, concentration and pressure dependences of the broadening coefficient were realized for five lines at room temperature. The results are compared with previous experimental data and also calculations. Our coefficients of collisional broadening, γ 0 , obtained at different temperatures as well as the temperature dependence parameter, n, are in satisfactory agreement with previous studies. The pressure broadening coefficients, γ 0 , are usually in good agreement with those reported for the same and other vibrational bands, indicating that they are insensitive to vibrational excitation. The pressure shift coefficients, δ 0 , by contrast, were found to differ substantially among vibrational bands.

Inspired by the recent experimental data (Phys. Lett. B {\bf 675} (2009) 420), we extend the triaxial projected shell model approach to study the $\gamma$-band structure in odd-mass nuclei. As a first application of the new development, the $\gamma$-vibrational structure of $^{103}$Nb is investigated. It is demonstrated that the model describes the ground-state band and multi-phonon $\gamma$-vibrations quite satisfactorily, supporting the interpretation of the data as one of the few experimentally-known examples of simultaneous occurrence of one- and two-$\gamma$-phonon vibrational bands. This generalizes the well-known concept of the surface $\gamma$-oscillation in deformed nuclei built on the ground-state in even-even systems to $\gamma$-bands based on quasiparticle configurations in odd-mass systems., Comment: 10 pages, 3 figures

Collective bands in the neutron-rich 103 Nb nucleus have been investigated by measuring prompt γ -rays following spontaneous fission of 252 Cf. Three new bands have been identified. The band based on the 716.8 keV level is proposed as a candidate for the K π = 9 / 2 + one-phonon γ -vibrational band, and the band built on the 1282.1 keV level is proposed as a candidate for the K π = 13 / 2 + two-phonon γ -vibrational band. The two-phonon γ -vibrational band is the first such band identified in odd- Z nuclei.

A white colour IL-SiWA hybrid molecular material has been synthesized using 1-butyl 3-methyl imidazolium bromide ionic liquid and silicotungstic acid. The material is found to dissolve in polar organic solvent such as DMSO, but not in water. It is characterized by CHN analysis, FTIR, XRD, UV-vis DRS, TGA and SEM. The FTIR spectra indicate the formation of a hybrid compound showing fingerprint vibrational bands of both Keggin ions of silicotungstic acid and imidazolium ions. There is a strong evidence of interaction between the Keggin anions and imidazolium cations from the UV-vis DR spectra and the splitting of imidazolium C-H bands in the IR spectrum of the IL-SiWA. The near IR shows loss of crystallization water from heteropoly acid when it reacts with ionic liquid forming the hybrid molecular material. � 2008 Elsevier B.V. All rights reserved.

Optical emission spectroscopy of atomic lines and molecular vibrational bands in N2, H2/N2 and Ar/N2 plasmas at steel nitriding conditions have been reported as an application of this diagnostic to plasma nitriding. An increase in Ar I intensity as Ar percentage increases in an Ar/N2 mixture is observed, while the effect on N2+ emission has a decrease, just the reverse of Ar I emission profile. As electron energy distribution function, EEDF, shifted to high electron energy as Ar percentage increases in the mixture, the presence of high-energy electron at high gas temperature of discharge can be predicted. It has also been found that pressure effect on N2+ band in pure nitrogen plasma is to increase the band intensities. Spatial distribution of N2+(0,1) and N2+(0,2) emission profile in N2/H2 mixture reveals shrinking of negative glow by 10 mm in the presence of 10% H2 and 90% N2 relative to a pure N2 plasma.

Analysis of the vibrational properties of Langmuir–Blodgett multilayers of the perylenediimide–fullerene (PDI–C 60 ), perylenediimide–tetrathiafulvalene (PDI–TTF) dyads, and reference molecules adsorbed on various surfaces was performed. The comparison of their absorption and reflection–absorption spectra suggests small redistribution of the charges in both moieties of the dyads after formation of the Langmuir–Blodgett layers. This effect is observed as shifts of selected vibrational bands of the dyad layers in comparison with respective bands of the dyads in the bulk. Orientations of organic chain molecules grafted to a metal surface were suggested on the ground of IR reflection–absorption investigations.

Experiments on 2-pyridone (2PY) [Y. Matsuda, T. Ebata, N. Mikami, J. Chem. Phys. 113 (2000) 573; J.A. Frey, R. Leist, C. Tanner, H.M. Frey, S. Leutwyler, J. Chem. Phys. 125 (2006) 114308] have revealed that specific vibrational bands in the laser-induced fluorescence spectrum are missing in comparison to the fluorescence depletion spectrum. The possibility of mode-induced non-radiative decay has been raised in order to explain the effect. In the present work, this hypothesis is tested by an extensive investigation of the excited-state energy surfaces of 2PY by means of multireference ab initio methods. Several conical intersections have been located and the paths connecting them to the minimum on the S 1 surface have been explored. Mixed quantum-classical dynamics simulations were used to estimate how the bias towards specific modes can modify the non-radiative decay rate. These investigations nicely confirm the proposed mode-induced non-radiative decay mechanism.