Vibration and vibronic spectra of lanthanide compounds with different types of coordination polyhedra of tungsten and molybdenum.

Luminescence excitation vibronic spectra as well as IR and Raman spectra of about 50 primary, binary and ternary lanthanide tungstates and molybdates and compounds with mixed anions (doped by Eu3+ ions) relating to about 15 structural types were analysed. Correlation of the types of isolated and joint coordination polyhedra of tungsten or molybdenum with details of the vibration and Eu3+ vibronic spectra was investigated.

Vibronic interaction in europium nitrates Eu(NO3)3 x 4SOR2.

Luminescence and excitation of luminescence vibronic spectra of europium nitrates Eu(NO3)3 x 4SOR2 containing sulphoxide derivatives were obtained and analysed. Some factors influencing the intensity distribution in vibronic sidebands are discussed. Significant variation of the intensity distribution in antiStokes sidebands of Eu3+ electronic transitions in series of nitrates results from the difference in effective charges on coordinated oxygen atoms of ligands. Another important detail of the vibronic spectra is a redistribution of intensity in the region of 5D0, 5D1-->7F2 transitions of luminescence spectra originated in overlap of different vibronic transitions. Mixing between the 7F2 electronic state of Eu3+ and vibronic satellites of 7F0 electronic state was studied both under conditions of resonance and in case of significant detuning.

[Conformation of lanthanide complexes with Schiff bases of pyridoxal and dipeptides]. / Konformatsiia kompleksov lantanidov s shiffovymi osnovaniiami piridoksalia i dipeptidov.

In order to simulate the active centres of pyridoxal enzymes, lanthanide complexes of pyridoxal-dipeptide (gly-asn) azomethines were investigated by means of NMR 1H and optical spectroscopy. NMR spectra were shown to correspond to conformation averaged over two positions of the ion. The ion was bound to the oxygen atom of PL and nitrogen atom of azomethine. In addition, it coordinates the oxygen atom of the peptide bond or the asparagine carboxyl.

[Nucleotide conformation in aqueous solutions by the NMR spectrum lanthanide shift method]. / Issledovanie konformatsii nukleotidov v vodnykh rastvorakh metodom lantanidnogo smeshcheniia spektrov IaMR.

Nucleoside triphosphates, ATP in particular, are investigated by 1H and 31P NMR with lanthanide perchlorate as LSR. The nucleotide base is shown to be near the phosphate groups. Dinucleotides and nucleoside monophosphates are investigated by means of a new LSR--lanthanide complex of pirydoxalidenaspartic acid. NAD+ and its derivatives are shown to exist in folded conformation at high pH values. AMP is shown to undergo conformational change in the pH range between 7 and 8.5. The structure of adduct of new LSR with amino acid is calculated in assumption of unaxial symmetry of the magnetic dipolar interaction. Parameters of the interaction were determined from optical spectra.

[Use of rare earth elements as markers for the study of biologically active compounds. V. Luminescence spectra and binding centers of europium in proteins]. / Primenenie redkozemel'nykh élementov v kachestve metki dlia issledovaniia biologicheskie aktivnykh soedinenii. V. Spektry liuminestsentsii i tsentry sviazyvaniia evropiia v nekotorhykh belkakh

Luminescence spectra of europium ions bound to some proteins are investigated. Europium is shown to coordinate no more than two charged groups, first of all carboxyles. The possibility of more specific coordination of rare earths in proteins is discussed.

[Use of rare-earth elements as labels for studying biologically active compounds. IV. Luminescence spectra and structure of compounds of europium with nucleotides]. / Primenenie redkozemel'nykh élementov kak metki dlia issledovaniia biologicheski aktivnykh soedinenii. IV. Spektry liuminestsentsii i stroenie soedinenii evropiia s nukleotidami

Spectra of europium coordinating nucleotides are investigated. Europium is shown to coordinate phosphate, but the way of coordination may change. Conditions of nitrogen bases coordination are determined. The evidence or the existence of coordinated immobilized water is found.

[Application of rare-earth elements as labels in studying biologically active compounds. III. Natural and magnetic circular dichroism of complexes of rare-earth elements with pyridoxalidene amino acid complexes]. / Primenenie redkozemel'nykh élementov v kachestve metok dlia issledovaniia biologicheski aktivnykh soedinenii. III. Estestvennyi i magnitnyi krugovoi dikhroizm kompleksov RZE s piridoksalidenaminokislotami

Circular dichroism of pyrodoxalidenaminoacid complexes with rare earths and other metals and magnetic circular dichroism of several neodimium complexes are investigated. CD spectra of the complexes of the rare earths with azometines made of different amino acids could be classified into four groups. Some of the CD spectra are shown to be individual. The dependence of the CD spectra on the rare earch ion dimension is considered. Coordination of the rare earth ions is shown to be the same as in the case of zinc, cobalt, iron or copper.

[Application of rare-earth elements as labels in studying biologically active compounds. I. Luminescence spectra of solutions of complexes of pyridoxaldiene amino acids with europium]. / Primenenie redkozemel'nykh elementov v kachestve metki dlia issledovaniia biologicheski aktivnykh soedinenii. I. Spektry liuminestsentsii rastvorov kompleskov piridoksalidenaminokislot s evropiem

The luminescence spectra of qater solutions of europium complexes with azometines formed by condensation of amino acids with pyrydoxal are investigated. The differences in luminescence spectra connected with the variations in the complexes structures are found. The possibilities of application of the europium ions luminescence for biochemical reactions investigation and for structure studies and identification of biologicaly active compounds are discussed.

[Application of rare-earth elements as labels in studying bilogically active compounds. II. Luminescence spectra and structure of europium complexes for use as shift reagents in NMR studies]. / Primenenie redkozemel'nykh élementov v kachestve metki dlia issledovaniia biologich'ski aktivnykh soedinenií. II. Spektry liuminestsentsii i stroenie kompleksov evropiia primenimykh v kachestve shift-reagentov pri issledovaniiakh metodom IaMR

The luminescence spectra and solubility of several europium complexes are investigated. The conditions put upon the complex structure for its successful use as a shift reagent are discussed. Some water-soluble europium complexes with pyridoxaliden amino acids are shown to be fit as possible shift reagents.