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We theoretically observe the cyclotron–phonon resonance (CPR) in monolayer silicene by considering the magneto-optical absorption power (AP) of the system. The AP is calculated utilising the projection operator technique when a static magnetic field is subjected perpendicularly to the plane of the material and the electron–optical phonon scattering is involved. The absorption spectra show the resonance behaviour where the photon energies at resonant peaks satisfy the cyclotron–phonon (CPR) conditions in which the CPR energy depends linearly on the square root of the magnetic field strength. This dependence is similar to that in graphene and different from that in monolayer MoS 2 and conventional low-dimensional semiconductors. The dependence of the full-width at half maximum (FWHM) on the magnetic field strength has the laws similar to those obtained for graphene and monolayer MoS 2. However, the FWHM value in silicene is two times smaller than it is in graphene and has the same order as it does in monolayer MoS 2. At relatively high temperature (T > 300 K), the FWHM for phonon emission differs very little from that for phonon absorption and becomes identical in two cases when T > 350 K. • The cyclotron–phonon resonance is observed in the absorption spectra. • The CPR energy is proportional to the square root of magnetic field strength. • The FWHM is proportional to the square root of magnetic field strength. • The FWHM increases slightly with increasing temperature. • At high temperatures the roles of phonon emission and phonon absorption are identical. [ABSTRACT FROM AUTHOR]

Abstract: The absorption spectrum of ozone,16O3, has been recorded in the 6220–6400cm−1 region by high sensitivity CW-cavity ring down spectroscopy (α min ∼3×10−10 cm−1). 1836 rovibrational transitions have been assigned to the 2ν 2 +5ν 3, 5ν 1 + ν 3 and 2ν 1 + 2ν 2 +3ν 3 A-type bands centred at 6305, 6355 and 6387cm−1, respectively. In addition, 99 lines of the very weak ν 1 +2ν 2 + 4ν 3 and 4ν 1 +3ν 2 B-type bands are identified. The modeling of the observed spectrum in the effective Hamiltonian approach was particularly laborious and complex as several rovibrational interactions of both Coriolis and anaharmonic type were found to be of importance, in particular for the (124) vibrational state. Nevertheless, it has finally been possible to fit the 990 experimentally determined energy levels with an rms deviation of 8.29×10−3 cm−1 and to derive the transition moment parameters allowing a satisfactory reproduction of the observed intensities. As the differences in positions between the final calculations and observations are still larger than the experimental accuracy, we provide the list of all energy levels derived from the observation, in addition to their differences with the calculated ones. These experimental energy levels, with the transition moment parameters were used to generate a line-list of 2451 transitions, reproducing the observed spectrum. This list is given as Supplementary Material. [Copyright &y& Elsevier]

Abstract: A recently constructed long-path enclosive flow cooling apparatus is employed to obtain the Fourier transform gas-phase infrared absorption spectrum of natural isotopic trans-1,2-dichloroethylene with a resolution of 0.00190cm−1 in the 800–1000cm−1 spectral region. The rotational structure of the out-of-plane CH flapping fundamental has been analyzed for the isotopic analogues 35Cl2 and 35Cl37Cl using the Watson A-reduced Hamiltonian model and I r -representation. A ground-state combination difference analysis for the 35Cl37Cl isotopomer based on 1402 assigned transitions belonging to the ν 6 band yields a band origin of 897.94493(10)cm−1 and values for the ground-state rotational constants: A 0 =1.7466454(44)cm−1, B 0 =0.05019643(82)cm−1 and C 0 =0.04877977(82)cm−1 together with quartic centrifugal distortion constants. The red-shift of 0.00444(10)cm−1 observed for the ν 6 band origin of 35Cl37Cl relative to the 35Cl2 band origin is now consistent with the Rayleigh rule. [Copyright &y& Elsevier]

Abstract: The absorption spectrum of ozone, 16O3, has been recorded in the 5980–6220cm−1 region by high sensitivity CW-Cavity Ring Down Spectroscopy (α min ∼3×10−10 cm−1). This study extends a first investigation with the same experimental set-up limited to the 6030–6090cm−1 spectral region [M.-R. De Backer-Barilly, A. Barbe, Vl.G. Tyuterev, D. Romanini, B. Moeskops, A. Campargue, J. Mol. Struct. 780–781 (2006) 225–233] where the analysis of two A-type bands was reported, using FTS spectra for complementary information. The spectral extension of the recordings allows not only to enlarge considerably the observed transitions of these two bands, but more importantly, to assign four new bands: the 3ν 2 +4ν 3,5ν 1 + ν 2 and ν 1 +2ν 2 +4ν 3 B-type bands which were considered as dark in our previous report and the 3ν 1 +3ν 2 + ν 3 A-type band. The high mixing of the observed states approaching the dissociation limit, leads to the breakdown of the polyad structure and ambiguities in the vibrational labelling which are discussed. Finally, 1789 transitions were assigned, and a suitable Hamiltonian model allows reproducing correctly the observations for five of the six observed bands. The list of 1004 experimentally determined energy levels is provided. The determined effective Hamiltonian and transition moment operators were used to generate a list of 5338 transitions given as Supplementary Material. It is interesting to note that the d 5 parameter of the effective transition moment is of great importance to account for the observed intensities of the B-type bands. [Copyright &y& Elsevier]

Abstract: A series of five carefully designed tris(phthalocyaninato) gadolinium triple-decker complexes [Pc(R)8]Gd[Pc(R′)8]Gd[Pc(R″)8] (; , ; , ; R=H, ; ) (1–5) were prepared and the film forming properties on water surface were systematically investigated. The limited mean molecular area obtained by isotherms revealed an “edge-on” conformation for all these compounds. UV–vis absorption spectra showed red-shifted Q bands, indicating the formation of J aggregates and effective intermolecular interaction in solid film. Phthalocyanine rings were found to take tilted orientation with respect to the normal of substrate according to the polarized absorption spectroscopic measurements. Low angle X-ray diffraction results provide direct evidence and therefore clearly clarify the point, for the first time, that unsymmetrical triple-decker molecules pack on the water surface with the unsubstituted phthalocyanine ring set close to the water surface and the substituted phthalocyanine ligand with octyloxy groups lies on the top. [Copyright &y& Elsevier]

Abstract: On the basis of UV–Vis absorption spectra from 33 aqueous solutions with a multivariate composition in uranium (VI), sulfate, and hydroxide, the evaluation of a complete measurement uncertainty budget of relevant physicochemical quantities describing the system is performed. The analysis was performed by threshold bootstrap computer-assisted target factor analysis and revealed the presence of the species . The analytical procedure is scrutinized to identify and quantify relevant influence factors on the basis of cause-and-effect analysis. The complete measurement uncertainty budgets are obtained as empirical cumulative distribution functions, which show a marked non-Normality. Evidence is given that the apparent discrepant results reported in the literature, especially for formation constants of species , are not a result of faulty experimentation but of neglect of relevant uncertainty contributions. Thus, reliability has been considerably overestimated – making the results of different independent studies incompatible. [Copyright &y& Elsevier]

Abstract: The absorption spectra of carbon dioxide in natural isotopic abundance and with 99% enrichment in 13C have been recorded by CW-cavity ringdown spectroscopy in two specific spectral regions: 5957–6122 and 6745–6833cm−1. The spectra were obtained at Doppler limited resolution by using a CW-CRDS spectrometer based on fibered DFB lasers. The typical sensitivity of 5×10−10 cm−1, allowed for the detection of lines with intensity as weak as 5×10−29 cm/molecule. More than 2900 line positions of the six major isotopologues contributing to the spectra (12C16O2, 16O12C17O, 16O12C18O, 13C16O2, 16O13C17O and 16O13C18O), were measured and assigned on the basis of their respective global effective Hamiltonian models. For comparison, only 507 lines are provided by the HITRAN database in these spectral regions. The band by band analysis has led to the determination of the rovibrational parameters of a total of 52 bands, 30 of them being newly reported. Most of the observed line positions show an agreement close to the experimental uncertainty (1–2×10−3 cm−1) with the predictions of their respective effective Hamiltonian models. However, the quality of the predictions degrades for the minor isotopologues reaching maximum deviations of 0.35cm−1 in one specific case. For several bands, rovibrational transitions with J values between 60 and 90 could be newly detected. While an excellent agreement is observed with the line positions predicted by the Hamiltonian models, the comparison of these observations with the line positions listed in the HITRAN database or extrapolated by using the best FTS rotational constants available in the literature has evidenced significant deviations. [Copyright &y& Elsevier]

Abstract: Spectra of the B 3Σ−–X 3Σ− transition in SO above the first dissociation limit are recorded using degenerate four wave mixing. These spectra are combined with earlier work involving laser induced fluorescence, absorption spectra and Fourier transform emission spectra, to enable a rotational analysis and deperturbation of vibrational levels of the B state up to v′=16. Numerous perturbations were noted within the B 3Σ− state, and the origin of these is discussed. In a number of cases, these perturbations can be attributed to interactions with specific other electronic states of SO, such as A 3Π, C 3Π, d 1Π, and A″3Σ+. [Copyright &y& Elsevier]

Abstract: Over 8000 line positions and intensities of phosphine (PH3) at 3μm have been measured at 0.0115cm−1 resolution with the McMath-Pierce Fourier Transform spectrometer at Kitt Peak. The observed line intensities ranged from 4.13×10−6 to 4.69×10−2 cm−2 atm−1 at 296K, for line positions between 2724.477 and 3601.652cm−1. This region spans eight interacting vibrational states: 3ν 2 (2940.8cm−1), 2ν 2 + ν 4 (3085.6cm−1), ν 2 +2ν 4 (3214.9cm−1), ν 1 + ν 2 (3307.6cm−1), ν 2 + ν 3 (3310.5cm−1), 3ν 4 (∼3345cm−1), ν 1 + ν 4 (3426.9cm−1), and ν 3 + ν 4 (3432.9cm−1). Assignments have been determined for all the bands except 3ν 4 (a weak band in a highly congested area) for a total of 4232 transitions. The total integrated intensity for this region is 5.70cm−2 atm−1 near 296K, and assigned lines account for 79% of the observed absorption. The two strongest bands in the region are ν 1 + ν 4 and ν 3 + ν 4 with band strengths at 296K of 1.61 and 2.01cm−2 atm−1, respectively. An empirical database of PH3 line parameters (positions, intensities, and assignments) is now available. Lower state energies (corresponding to assignments from this study) and line widths from the literature are included; default values are used for unassigned features. [Copyright &y& Elsevier]

Abstract: Extension of the working frequency of modern resonator spectrometers into submillimeter wave range is described. Experimental record of atmospheric absorption spectrum covering 45–370GHz range is demonstrated for the first time, and measured water vapor J′ ka′, kc′–J ka, kc =51,5–42,2 at 325GHz line parameters are presented. For the first time pressure lineshift for the 325-GHz water vapor line is measured. Further extension of working range is discussed. New estimations of physical limits of time needed for measurements of absorption in the whole Backward Wave Oscillator (BWO) range are given for phase continuous synthesizer regime. Basic schemes of fast broadband continuous phase synthesized sources are discussed. Verification of the previous measurements of water vapor 31,3–22,0 at 183GHz line parameters is presented. Comparisons with ringdown resonator spectrometers are given. [Copyright &y& Elsevier]

Abstract: The mid-infrared (1500–3800cm−1) absorption spectrum of gaseous nitric oxide has been studied at low temperature (99K) with a long absorption path (160m) in order to observe weak combination, difference, and overtone bands of the NO dimer. About ten new bands were assigned with greater or lesser certainty. Combined with previous results, they lead to a set of 12 secure and 7 tentative vibrational term values for (NO)2, essentially doubling our knowledge of NO dimer vibrational states. The strongest non-fundamental bands in this region, other than the ν 1 (symmetric N–O stretch)+ ν 5 (asymmetric N–O stretch) overtone, involve combinations of ν 5 with ν 3 (intermolecular stretch). Excitation of ν 5 results in increased frequencies for the intermolecular modes ν 2, ν 3, and ν 4. A new value of 155.5cm−1 was obtained for ν 4, the elusive infrared-inactive out-of-plane fundamental vibration. [Copyright &y& Elsevier]

Abstract: The absorption spectrum of the natural sample of nitrous oxide has been recorded at Doppler limited resolution with a Fourier-transform spectrometer in the spectral range 5000–10000cm−1. Ten cold bands (8Σ−Σ and 2Σ−Π), thirteen hot bands (11Π−Π, Σ−Σ, and Δ−Δ) of 14N2 16O and the 3ν 3 band of 14N15N16O have been newly detected. The uncertainty of the line position determination is estimated to be about 0.005cm−1 for unblended lines. The assignment of the spectrum has been done with the help of the prediction performed within the framework of the polyad model of effective Hamiltonian. The spectroscopic parameters G v , B v , D v , H v , and q v have been determined for all newly detected bands. The line intensities of 13 weak bands have been measured. The uncertainty of the obtained line intensity values varies from 7 to 13%. [Copyright &y& Elsevier]

Abstract: Using water/AOT/n-octane reversed micelle as the medium, the optical signal of the reactive intermediate of laccase-catalyzed oxidation of o-phenylenediamine, which was indetectable in aqueous solutions, was successfully captured. Thus online kinetic studies of the intermediate were accomplished. Two-way kinetic spectral data were acquired with stopped-flow technique. By resolving the data with global analysis software, both the kinetic curves and the absorption spectra of the components involved in the reaction process were simultaneously obtained. The whole reaction in the reversed micelle was proved to be composed of two successive steps, an enzymatic generation of the intermediate and a following nonenzymatic decay of the intermediate. A consecutive first-order kinetic model of the whole reaction was confirmed. The influences of microenvironmental factors of the medium (such as the pH value of the water pool and the water/AOT ratio) on the detection of the intermediate were also investigated. [Copyright &y& Elsevier]

Abstract: The weak absorption spectrum of monodeuterated water, HDO, has been recorded by intracavity laser absorption spectroscopy (ICLAS) between 11645 and 12330cm−1. This spectrum is dominated by the ν 2 +3ν 3 band of HDO at 11969.76cm−1. A total of 497 energy levels belonging to 12 vibrational states were determined while only 140 levels were previously reported from a recent investigation by Fourier transform spectroscopy in the same spectral region. The rovibrational identification process of the 1378 lines assigned to the HDO isotopologue was mostly based on the results of the accurate variational calculations of Schwenke and Partridge. The overall agreement between these calculations and the observed spectrum is very good. However, strong discrepancies in the calculated line intensities were evidenced in a few cases corresponding to an intensity transfer to a dark state through local resonance interaction. [Copyright &y& Elsevier]

Abstract: Large-scale CdS nanowires with uniform diameter and high aspect ratios were synthesized using a simple solvothermal route that employed CdCl2 and S powder as starting materials, ethylenediamine (en) as the solvent. X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) images show that the products are hexagonal structure CdS nanowires with diameter of 40nm and length up to 10μm. Selected area electron diffraction (SAED) and high resolution TEM (HRTEM) studies indicate the single-crystalline nature of CdS nanowires with an oriented growth along the c-axis direction. The optical properties of the products were characterized by optical absorption spectra and photoluminescence spectra. Based on the results of contrastive experiments, it is found that the sulfur source and the solvent play significant roles in the formation of uniform nanowires. A possible formation mechanism of nanowires is discussed. [Copyright &y& Elsevier]

Abstract: A relatively narrow diffuse band at about 212.5nm was observed in both emission and absorption spectra of the cadmium vapour. The band was identified as a transition involving the 1 u Rydberg state correlated with the asymptote 63 S 1 +51 S 0 and the ground state of Cd2. Analysis yielded some data concerning the previously unknown outer potential energy well of the upper state and the oscillator strength f (R). [Copyright &y& Elsevier]

Abstract: Using circular dichroism (CD) and electronic absorption spectroscopy techniques, interaction of the natural dietary cis-carotenoid bixin with an important human plasma protein in vitro was demonstrated for the first time. The induced CD spectra of bixin obtained under physiological conditions (pH 7.4, 37°C) revealed its binding to the serum acute-phase reactant α1-acid glycoprotein (AGP), a member of the lipocalin protein family. Spectral features of the extrinsic Cotton effects of bixin suggested the inclusion of a single, chirally distorted ligand molecule into the asymmetric protein environment. Compared with the absorption spectra obtained in ethanol and benzene, the strong red shift of the main absorption peak of AGP-bound bixin indicated that the proposed binding site was rich in aromatic residues, and also suggested that hydrophobic interactions were involved in the binding. Using the data obtained from the CD titration experiments, the association constant (K a =4.5×105 M−1) and stoichiometry of the binding (0.15) were calculated. The low value of the stoichiometry was attributed to the structural polymorphism of AGP. To the authors’ knowledge, the current study represents the first human lipocalin protein for which carotenoid binding affinity has been explored in vitro with these techniques. [Copyright &y& Elsevier]

Highly purified single crystals of pyrene were made by a gas phase crystal growth method from 180 times of zone-refined pyrene. The absorption spectra of the single crystal have been transformed from the reflection spectra between 2.5 and 6.5 eV at 2, 77 K and room temperature. The dry powder of β-cyclodextrin including pyrene single molecule were prepared in vacuum to investigate the electronic states of the isolated molecule. The absorption spectra of the single molecule show similar spectra to those of the single crystal. The pyrene molecule keeps its electronic character even in the single crystal. [Copyright &y& Elsevier]

The 0310 ← 0110 parallel Q branch of N2O has been studied at 297 K and over the pressure range 1–130 torr. Absorption spectra were recorded using a high resolution (1.5 MHz or 5 × 10-5 cm-1) and high signal-to-noise (>3500:1) mid-infrared spectrometer based on difference-frequency infrared generation in AgGaS2. In the low-pressure range (1–11 torr) we obtained accurate values for the line strengths, the broadening coefficients, the weak mixing coefficients, and the overall shifting of the branch. The medium pressure results, ranging from 23 to 130 torr, were analyzed by treating the band as a whole, using a relaxation matrix formalism, based on an energy gap scaling law. We find, effectively, that only 36% of the rotationally inelastic collisions are associated with Q branch mixing, the rest presumably being associated with Q–P and Q–R mixing in the same vibrational band. The pressure shifting coefficient of the 0310 ← 0110 Q branch as a whole was also determined and found to be 5.8 × 10-3 cm-1/atm towards lower frequencies. [Copyright &y& Elsevier]