摘要:

The Fourier transform infrared and Raman spectra of newberyite, MgHPO4·3H2-O, were studied in the 2000-370 cm-l region. Also investigated were the spectra of a series of partially deuterated analogues. By comparing the spectra recorded at room temperature and those obtained at the boiling temperature of liquid nitrogen and by studying the spectra of the series of partially deuterated newberyite an assignment was proposed for the observed bands. The spectra are fully in line with the crystallographic data and prove that the title compound is a true crystalline hydrate and does not contain H3O+ions in its structure.

ISSN:0038-7010    

DOI:10.1080/00387019909350019

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The modern intracavity laser method has been applied to study electronic spectra of the hafnium monohalides molecules. Results of new investigation of HfF and HfBr molecules are presented: the bands at 589.3, 590.6, and 593.1 nm observed in intracavity laser spectra of HfF4have been assigned to the bands of HfF or ionized HfF; new molecular constants of the HfBr molecule have been obtained. Spectroscopic studies of HfCl and Hfl molecules are discussed, and the most reliable molecular constants of HfCl, HfBr, and Hfl molecules are recommended.

ISSN:0038-7010    

DOI:10.1080/00387019909350020

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The Ni and new Cd and Co complexes of sulfadimethoxine (SDMX) are prepared and investigated their structural changes and stability by heating at different temperatures. The investigations were earned out by means of the infrared spectroscopy (IR) after heating the samples at several temperatures in the range 50-300 °C for an hour. The IR spectra of the heated samples at different temperatures have been compared with those at room temperature. The changes in the fundamental vibrational bands in their IR spectra gave the temperature values at which the samples decomposited. As a result, it is found that the stability of the complexes are higher than SDMX and their stability is in the order Ni > Co> Cd which depends on the second ionization potential of the metals.

ISSN:0038-7010    

DOI:10.1080/00387019909350021

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Eu3+ion emission spectra and luminescence lifetimes were investigated for EuCl3-nH2O (n=0,1,2,3,6). Each compound exhibited a characteristic set of emission bands and a specific luminescence lifetime. The number of water molecules and chloride ions coordinated to the Eu3+ion in these materials was estimated from the observed lifetimes, spectroscopic implications, and expected lanthanide coordination numbers. Approximation of the observed luminescence decay constant for each material was possible through the use of arithmetic terms associated with both the complexed water molecules and the complexed chloride ions which make up the inner-coordination sphere of the Eu3+ion.

ISSN:0038-7010    

DOI:10.1080/00387019909350022

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Time-resolved linear dichroism spectroscopy allows the relative transition moment vectors of the S1→ Sn, transitions to be obtained. This information can be used to aide in the assignment of the observed excited state and ground state transitions. The transition moment directions are constrained by the symmetry of the absorbing chromophore such that structural changes on the excited state surfaces can also be observed. The time dependence of the dichroism is related to the solution dynamics through the measurement of rotational correlation times. The spectroscopy of l,2:5,6-dibenzanthracene is presented as an example of these measurements.

ISSN:0038-7010    

DOI:10.1080/00387019909350023

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The electronic absorption spectrum of the title crystal of the clathrate compound of [Ni(en)2(NCS)2], C6JH6has been measured. The experimental results are discussed quantitatively with ligand field theory(LFT) and the radial wave function of non-free nickel(II) ion. The calculation values coincide well with the experimental results. In particular, they provide significant correlation between the electronic absorption spectrum and the crystal structure of the compound.

ISSN:0038-7010    

DOI:10.1080/00387019909350024

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

IR spectroscopy method has been designed in order to determine the average molecular weight of polysulfide polymers of the general formula:

ISSN:0038-7010    

DOI:10.1080/00387019909350025

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The adduct formation between CD3CN and the Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Sr2+, Mn2+, Fe2+, Cu+, Cu2+, Zn2+, Au+, Ag+, Cd2+, Hg2+and Tl3+cations has been investigated by FTIR spectroscopy. The v2vibrational mode, mainly consisting of the CN stretching vibration, was studied. Upon adduct formation with a Lewis acid this band shifted to higher frequencies relative to that of pure CD3CN. In spite of the widely varying electronic configurations of the cations studied, this frequency shift was found to' be approximately proportional to the polarizing power of the cation, measured as the charge to squared radius ratio, suggesting that the cation-acetonitrile interaction is of mainly electrostatic nature. No evidence of π back-donation was detected.

ISSN:0038-7010    

DOI:10.1080/00387019909350026

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Fourier-transform IR frequencies and integrated intensities of the cyano groups of a series of benzylidenemalononitriles (34 compounds) have been measured in dimethyl sulphoxide. Excellent and satisfactory correlations have been found between spectroscopic features and substituent constants. σ+(and other) constants of ionic substituents (three examples) have proved satisfactorily valid in the series studied. The C=C bridge transmits the substituent effects on the intensities twice as strong than the effects of the same substituents on the corresponding frequencies.

ISSN:0038-7010    

DOI:10.1080/00387019909350027

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Excitation energies, electromagnetic transition strength, and static moments in108,110,112,114,116CD nuclei are studied in the proton-neutron interacting boson model-2 (IBM-2). The calculations were carried out by using an improved version of the NPBOS code. The calculated values for Cd isotopes and the experimental ones agree. For the excitation energies the splitting of the 2-phonon multiplet was found rather small. In order to locate the Cd nuclei on the map of the IBM-2 parameters, the branching ratios were examined. It is found that Cd nuclei are classified in the U(5) limit.

ISSN:0038-7010    

DOI:10.1080/00387019909350028

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor