Joint Rotational Analysis of 16 Vibrational States of HDSe

High-resolution Fourier transform spectra of HD⁸⁰Se in the region of the ν₁+ν₃, 2ν₂+ν₃, 2ν₁+ν₂, 3ν₁, and ν₂+2ν₃ absorption bands, with centers located between 4000 and 5500 cm⁻¹, were recorded and rovibrationally analyzed. Energies of the (101), (021), (210), (300), and (012) states, together with those of the formerly reported (010), (100), (020), (001), (120), (110), (030), (011), (200), (002), and (003) states, were jointly used as input information in a “global fit” procedure. This fit provided 161 spectroscopic parameters which reproduce 3323 observed energies with accuracies close to experimental uncertainties. These parameters are compared with those predicted from H₂Se. Moreover, experimental band centers for HSeD are compared with those calculated theoretically.     

The Vibrational Spectra of a Series of Simple Phosphorus/Chromium Polyoxoanions

The infrared and Raman spectra of polycrystalline samples of K₂HPCr₂O₁₀, Na₃PCr₃O₁₃.3H₂0, K₃PCr₄O₁₆ and (NH₄)₃PCr₄O₁₆ were recorded and discussed. A general vibrational assignment for the internal vibrations of these species is proposed.

The structural characteristics of an interesting series of simple polyoxoanions of the PCr_nO^3- _3n+4 type have been determined recently^1–7. These species are essentially built from a central PO₄ -tetrahedron which share a different number of corners with CrO₄ -tetrahedra.

As part of our present studies on different physico-chemical properties of polyoxoanions, we have investigated the vibrational spectra of crystalline species containing the following anions: HPCr₂O^2- ₁₀, PCr₃O^3- ₁₃ and PCr₄O^3- ₁₆.

As the three species have some common structural features, their vibrational spectra can be analyzed and compared in terms of these common building elements, i. e., terminal CrO₃ and PO groups and POCr bridges.

The interatomic distances in the above mentioned units are also very similar in all the anions and the Cr-O distances are similar to those found in the normal (triclinic) form of K₂Cr₂O₇ ⁸.     

The Vibrational Spectra of Complexes with Planar Monothiooxamides. III. The Palladium(II) Complexes of Neutral Monothiooxamides

The new complexes trans-[PdX₂(H₄MTO)2] (X = Cl, Br, I), trans-[PdX₂(H₃MMTO)2] (X = Cl, Br, I), trans-[PdX₂(SH₃)2] (X = Cl, Br), [Pd(H₄MTO)₄]CI₂ and [Pd(H₃MMTO)₄]CI₂, where H₄MTO = monothiooxamide, H₃MMTO = N(o)-methylmonothiooxamide and SH₃ = N(s)-methylmonothiooxamide, have been prepared. The complexes were characterized by elemental analyses, conductivity measurements, X-ray powder patterns, thermal methods and spectroscopic (UV/VIS, FT-IR, Laser-Raman) studies. The vibrational analysis of the complexes is given using NH/ND and CH₃/CD₃ isotopic substitutions. Monomeric square planar structures are assigned for the complexes in the solid state. The neutral monothiooxamides behave as monodentate ligands coordinating through their thioamide sulfur atom. The complex [Pd(SH2)2] was isolated during the thermal decomposition of trans-[PdCl₂(SH₃)₂].     

Vibrational spectroscopic investigation of the hydrates of manganese(II) oxalate

The three known hydrates of manganese(II) oxalate, α‐MnC₂O₄ · 2H₂O, γ‐MnC₂O₄ · 2H₂O and MnC₂O₄ · 3H₂O were synthesized by known procedures and characterized by X‐ray powder diffractometry. Their infrared (IR) and Raman spectra were recorded and discussed on the basis of its structural peculiarities allowing to establish some interesting relations between them and with other, previously investigated, oxalate complexes. The IR spectra of partially deuterated samples of α‐MnC₂O₄ · 2H₂O were also discussed, reinforcing some of the performed assignments. Copyright © 2009 John Wiley & Sons, Ltd.     

Vibrational spectra of barium oxalate hemihydrate

The infrared and Raman spectra of barium oxalate hemihydrate, BaC₂O₄ · 0.5H₂O, were recorded and discussed on the basis of their structural peculiarities and in comparison with the spectra of the previously investigated calcium and strontium oxalates.     

High-Resolution Infrared Study of PHD2: The P-H Stretching Bands ν1 and 2ν1

For the first time the infrared spectrum of PHD₂ was recorded in the region of the PH stretching fundamental ν₁ at 2324.005 cm⁻¹ and the overtone 2ν₁ at 4563.634 cm⁻¹ with a resolution of 4.2×10⁻³ cm⁻¹ and 8.8×10⁻³ cm⁻¹, respectively. In the analyses about 1340 and 1020 transitions were assigned to the corresponding ν₁ and 2ν₁ bands, which provided 316 and 248 upper energies, respectively. Since both the bands are sufficiently isolated, a standard Watson-type Hamiltonian (A-reduction, I^r-representation) was employed. The obtained sets of spectroscopic parameters correlate very well both with each other, and with the corresponding parameters of the ground vibrational state.     

Cr3+/Tm3+/Ho3+共掺氟磷酸盐玻璃的制备及性能表征

制备了不同 Al(PO₃)₃含量的掺铥系列氟磷酸盐玻璃,研究了其结构、热稳定性和光谱性质. 研究了不同摩尔百分数 Al(PO₃)₃掺杂下 Cr³⁺/Tm³⁺/Ho³⁺共掺氟磷酸盐玻璃在 2.0μm 处的发光特性. 并且用Judd-Ofelt理论计算了强度参量,并由此计算了激发能级的自发辐射跃迁速率、辐射寿命、荧光分支比等光谱参量. 结果表明,随着 Tm³⁺浓度增加,2.0μm 处发光的强度逐渐增强. 证明了Tm³⁺(³F₄) →Ho³⁺(⁵I₇)能量转移是非常有效的,并与掺杂浓度有关. 关键词： 氟磷酸盐玻璃 能量传递 荧光光谱 吸收光谱     

Emission Mössbauer studies of 57Co2+ and 119Sb5+ adsorbed on γ-Fe2O3 and NiFe2O4 surfaces

Summary Surface chemical states of⁵⁷Co²⁺ and¹¹⁹Sb⁵⁺ ions adsorbed on γ-Fe₂O₃ and NiFe₂O₄ were studied in the presence of the aqueous phase using the magnetic interaction between the substrates and⁵⁷Fe²⁺ or¹¹⁹Sn⁴⁺ arising from the adsorbed species. Two chemical forms were observed for the⁵⁷Co²⁺ adsorbed on γ-Fe₂O₃; one giving a peak in the high-field region and another giving a broad distribution in the lower fields, which were attributed to⁵⁷Co²⁺ at surfaceB sites of the spinel structure of γ-Fe₂O₃ and⁵⁷Co²⁺ species weakly bonded to the substrate, respectively. In case of the NiFe₂O₄ substrate, the latter species was dominant and was converted to the former by heating. Most of the¹¹⁹Sb⁵⁺ ions adsorbed on the γ-Fe₂O₃ and NiFe₂O₄ particles were found to have a certain magnetic interaction with the magnetically ordered ions of the substrates. Paper presented at the ICAME-95, Rimini, 10–16, September 1995     

Er3+，Tm3+共掺的NaY(WO4)2晶体的光谱分析和上转换发光

在室温下，测量了Er:Tm:NaY(WO₄)₂晶体的吸收光谱、激发光谱、发射光谱以及上转换发光，并运用J-O理论对测量的结果进行了计算，得出了Er:Tm:NaY(WO₄)₂晶体的强度参数.报道了Tm，Er离子间特殊的能量传递和相关上转换，解释了离子间的能级跃迁过程.同时，对于Er增强Tm离子近红外发光的特性也作了充分研究. 关键词： 4)₂晶体')" href="#">Er:Tm:NaY(WO₄)₂晶体 吸收光谱 发射光谱 激发光谱 上转换     

Laser-induced breakdown spectra of Zn2 molecule in the violet region

Laser-induced breakdown spectrum has been recorded in the region of 380–455 nm using second harmonics of Nd:YAG laser, computer-controlled TRIAX 320 M monochromator with a reciprocal linear dispersion 2.64 nm/mm fitted with ICCD detector. The spectrum consists of 108 bands, which are classified into four new subsystems E0 _u ⁺ (¹Σ _u ⁺ ) → A1_g(³Π_g), J0 _g ^± \1_g(³Σ _g ⁺ ) → D1_u(¹Π_u), F1_u → A0 _g ^± (³Π_g) and F1_u → A2_g(³Π_g) along with additional bands of the known system E0 _u ⁺ (¹Σ _u ⁺ ) → A0 _g ^± (³Π_g). The molecular constants for these systems have also been determined.     

On the Determination of the Equilibrium Structure of the PH3 Molecule

Values of the r_e and α_e equilibrium structural parameters of the PH₃ molecule have been determined on the basis of experimental data on the fundamental bands of the PH₂D and PHD₂ species only, without any knowledge of the force-constant-type parameters of the PH₃ molecule. The functions of the equilibrium rotational parameters A^e, B^e, and C^e have been determined. These functions are totally independent of the values of any resonance interaction parameters. Then these functions have been used to determine r_e and α_e constants. The obtained values r_e=(1.416 776±0.000 164) Å and α_e=(93.56±0.29)° differ a little from those found in the earlier literature.     

IR Spectra of Be(IO3)2.nH2O (n = 4, O) and of the Deuterated Analogue

Abstract

The compounds of beryllium - Be(IO₃)₂.4H₂O, its deuterated analogue and Be(IO₃)₂ were studied by IR-spectroscopy over the range of 200 to 4000 cm^?1.     

Infrared and near infrared emission spectra of TeH and TeD

The vibration-rotation emission spectra for the X²Π ground state and the near infrared emission spectra of the X²Π_1/2-X²Π_3/2 system of the TeH and TeD free radicals have been measured at high resolution using a Fourier transform spectrometer. TeH and TeD were generated in a tube furnace with a DC discharge of a flowing mixture of argon, hydrogen (or deuterium), and tellurium vapor. In the infrared region, for the X²Π_3/2 spin component we observed the 1-0, 2-1, and 3-2 vibrational bands for most of the eight isotopologues of TeH and the 1-0 and 2-1 bands for three isotopologues of TeD. For the X²Π_1/2-X²Π_3/2 transition, we observed the 0-0 and 1-1 bands for TeH and the 0-0, 1-1, and 2-2 bands for TeD. Except for a few lines, the tellurium isotopic shift was not resolved for the X²Π_1/2-X²Π_3/2 transitions of TeH and TeD. Local perturbations with Δv = 2 between the two spin components of the X²Π state of TeH were found: X²Π_1/2, v = 0 with X²Π_3/2, v = 2; X²Π_1/2, v = 1 with X²Π_3/2, v = 3. The new data were combined with the previous data from the literature and two kinds of fits (Hund’s case (a) and Hund’s case (c)) were carried out for each of the 10 observed isotopologues: ¹³⁰TeD, ¹²⁸TeD, ¹²⁶TeD, ¹³⁰TeH, ¹²⁸TeH, ¹²⁶TeH, ¹²⁵TeH, ¹²⁴TeH, ¹²³TeH, and ¹²²TeH.     

Vibrational Spectroscopic Studies on the Dicyclopropylaminecadmium(II)Tetracyanometallate(II) Benzene Clathrates

ABSTRACT

New Hofmann–T_d-type clathrates of the forms Cd(CPA)₂M(CN)₄.C₆H₆ (CPA = cyclopropylamine; M?Cd or Hg) prepared in powder form and characterized by FT-IR, FT-Raman, far-IR spectra, X-ray diffraction, and elemental analyses are reported. Vibrational assignments are proposed for the bands of the host lattice and guest molecule. It is shown that the spectra are consistent with a proposed crystal structure for the compounds derived from X-ray diffraction measurements. The C, H, and N analyses were carried out for all the compounds. All the vibrational modes of coordinated CPA are characterized. The spectral features suggest that these compounds are similar in structure to the Hofmann–T_d-type clathrates.     

Study on the absorption characteristics and birefringence of Ce-doped SBN

Cerium-doped Sr_0.60Ba_0.40Nb₂O₆ (SBN:60) crystals were obtained by Czochralski method. Optical transmission spectra were measured and the absorption coefficients were calculated in the visible range. The results showed that Ce-doped crystals were transparent for wavelengths more than and the fundamental absorption edge shifted towards the longer wavelength direction with increasing Ce concentrations. In addition, the birefringence of crystals were investigated based on the theory of interference between extraordinarily and ordinarily polarized light, and the birefringence values were determined in the long wavelength region. As a result, the birefringence becomes larger by doping of SBN crystals with cerium.     

Vibrational Spectra of Arsenates and Phosphates of the Type Kcaln(XO4)2

The infrared and Raman spectra of polycrystal-line samples of different compounds of the types KCaLn(AsO₄)₂ and KCaLn(PO₄)₂, belonging to the hexagonal LaPO₄, structural modification, were recorded and discussed. A complete vibrational assignment, based on a factor group analysis, is proposed. The influence of the different lanthanide cations on the internal vibrations of the XO₄ groups is briefly discussed and some comparisons with related compounds are also made.

It is well known that simple lanthanide arsenates, phosphates, vanadates and cnromates (V) of the type LnXO₄ belong to two different structural types.     

Fourier Transform Infrared and Raman Spectra of 4-Vinylpyridine and its Transition Metal(II) Tetracyanonickelate Complexes

Abstract

Infrared and Raman spectra (4000-200 cm^?1) were recorded for 4-vinylpyridine and vibrational assignments made for fundamental modes on the basis of frequency shifts of the coordinated ligand, of the group vibrational concept and comparison with the assignments for related molecules. the infrared spectra of M(4-vinylpyridine)₂Ni(CN)₄ (M=Mn, Cd, Fe, Co, Ni or Cu) are reported.     

Vibrational spectra of the layered monofluorophosphate (V), NH4Ag3(PO3F)2

The powder Fourier‐transform (FT) infrared (IR) and Raman spectra of the recently characterized NH₄Ag₃(PO₃F)₂ were recorded and are discussed with a site‐symmetry analysis based on its known structural data. Some comparisons are made with the solution spectra of the PO₃F²⁻ anion and with those of crystalline Ag₂PO₃F. Copyright © 2009 John Wiley & Sons, Ltd.     

Deep-UV high resolution cavity ring-down spectroscopy of the Schumann-Runge bands in O2 and O2 at wavelengths 197-203 nm

With the use of a novel titanium:sapphire laser source delivering, upon fourth harmonic generation, narrowband and tunable radiation in the deep-UV, spectroscopic studies were performed on weak Schumann-Runge bands of oxygen. Improved values for rotational and fine structure molecular parameters for the , v = 0-2 states of ¹⁶O₂ were determined, as well as values for the v = 0-1 states in ¹⁸O₂. Signal detection was accomplished via cavity ring-down spectroscopy.     

Synthesis,Properties and Spectroscopic Studies of Cobalt (II) and Cobalt (III) Complexes with Planar Dithioxamides

The complexes [Coⁱⁱⁱ(LH₂)₃]X₃ (LH₂ = dithiooxamide, N-methyldithiooxamide, N,N′-dimethyldithiooxamide; X = Cl, Br, l) and [CoⁱⁱL]n have been prepared. They were characterized by analyses, thermal techniques, magnetic susceptibilities and spectroscopic (ligand-field, ¹³C-NMR, FT-IR) methods. The vibrational analysis of the prepared complexes is given using NH/ND and CH₃/CD₃ isotopic substitutions. The neutral dithiooxamides exhibit a bidentate chelating S,S-coordination, while the doubly deprotonated dithiooxamido anions act as bis-bidentate bridging S,N/N,S-ligands giving trans polymeric structures. The Co(III) complexes are octahedral with Co^IIIS₆ coordination spheres. A square planar geometry around Co(II) is assigned for the polymeric compounds.