Structures of Nitrate Complexes of Erbium in Aqueous Solutions.

Yokoyama, Haruhiko; Johansson, Georg; Persson, Per; Euranto, Erkki K.; Brekke, Trond; Aksnes, Dagfinn W.; Tokii, Tadashi

doi:10.3891/acta.chem.scand.44-0567

Cited by 23 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…20,21 Additionally, the absorption spectroscopic, 22,23 IR, 24 and NMR data 1,25 clearly suggested that nitrate ions form inner-sphere complexes with lanthanides. The radial distribution functions by X-ray diffraction results also supported this and were consistent with a bidentate and symmetric 26 or a monodentate and asymmetric 27 bonding of nitrate ions in the primary coordination sphere. However, the enthalpy and entropy data were interpreted in terms of outer-sphere ion pairs.…”

Section: Introductionsupporting

confidence: 73%

“…In the concentration range from 0.024 to 3 mol/ L, the slope values increased drastically, suggesting the lanthanum ions form nitrate complexes. As mentioned previously, X-ray diffraction 26 and the several spectroscopic methods 11,20,21,24,[32][33][34] indicated that lanthanide ions form inner-sphere complexes with nitrate ions, while the thermodynamic 28,29 and the dilatometric 35,36 data were interpreted in terms of the formation of outer-sphere ion pairs. In this study, there is no denying completely the existence of outer-sphere ion pairs, but the inner-sphere complex is considered to be the predominant species in the nitrate solution, since the large changes in the slope in this study are not explained by outer-sphere ion pairs.…”

Section: Resultsmentioning

confidence: 96%

See 1 more Smart Citation

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

1998

View full text Add to dashboard Cite

La NMR relaxations and chemical shifts in the aqueous nitrate and chloride solutions at 274-343 K were studied. The solutions in this study were La(NO 3 ) 3 -LiNO 3 or -HNO 3 , and LaCl 3 -LiCl 3 or -HCl systems. The dependencies of the slope for the plot of 1/T 1 (s -1 ) vs η/T (cP K -1 ) on the anion concentration showed that nitrate ions form inner-sphere complexes with lanthanum in a relatively low concentration but chloride ions scarcely form below about 4.3 mol/L. In the LaCl 3 -LiCl systems, the quadrupole coupling constants obtained by the temperature dependencies of 1/T 1 below about 4.3 mol/L ranged from 3.1 to 3.4 MHz, which agreed well with the value of hydrated lanthanum. In the LaCl 3 -HCl systems, however, the quadrupole coupling constants slightly increased with an increase in chloride ion concentration even below about 4.3 mol/L, indicating that chloride ions possibly begin to form inner-sphere complexes. Activation energies for the rotational motion of lanthanum were determined in all of the solutions by the T 1 analyses using the Arrhenius equation. The activation energies in the nitrate concentration range from 0 to 0.1 mol/L were about 14 kJ/mol and in that above 1 mol/L about 18 kJ/mol . On the basis of the quantitative analysis for the activation energies, these values were regarded as the energies for a breaking the hydrogen bond of H 2 O-H 2 O. While in the chloride ion systems, the activation energies gradually decreased above 0.6 mol/L, indicating that hydrated lanthanum ions are gradually removed from a net structure of the aqueous solution by being packed by chloride ions. Chemical shifts obtained from a series of experiments also showed that chloride ions do not form inner-sphere complexes with lanthanum below about 4.3 mol/L. Furthermore, the chloride ions induce downfield shifts and nitrate ions induce upfield relative to the value of hydrated lanthanum. It is likely that the downfield shifts in the chloride systems are due to the result of an overlapping closed-shell repulsion.

show abstract

Section: Introductionsupporting

confidence: 73%

Section: Resultsmentioning

confidence: 96%

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

1998

View full text Add to dashboard Cite

show abstract

“…After corrections for polarization and incoherent radiation, the observed intensities, I (s), where s = 4 7i sin d/k, were normalized to a stoichiometric unit volume (F) without correction for multiple scattering to obtain the reduced intensities, i'(s). The normalization procedure was performed by the highangle method [8][9][10]. Radial distribution functions, D (r), were calculated according to the standard proce dure described previously [8][9][10], where the modifica tion function, M(s), included the atomic scattering factor ( /) of oxygen and a damping factor of 100 pm2.…”

Section: Data Treatment and Analysismentioning

confidence: 99%

“…The normalization procedure was performed by the highangle method [8][9][10]. Radial distribution functions, D (r), were calculated according to the standard proce dure described previously [8][9][10], where the modifica tion function, M(s), included the atomic scattering factor ( /) of oxygen and a damping factor of 100 pm2. Spurious peaks below 100 pm in D (r) were removed to correct / (s) for low-frequency additions.…”

Section: Data Treatment and Analysismentioning

confidence: 99%

See 1 more Smart Citation

X-Ray Diffraction Study of the Solvation Structure of the Cobalt(II) Ion in N,N-Dimethylformamide Solution

Yokoyama

Suzuki

Goto

et al. 1995

Zeitschrift Für Naturforschung A

Self Cite

View full text Add to dashboard Cite

X -R a y D if fr a c tio n S tu d y o f th e S o lv a tio n S tr u c tu r e o f th e C o b a lt ( I I ) I o n in N ,N -D im e th y lf o rm a m id e S o lu tio n Haruhiko Yokoyama*, Saeko Suzuki*, Masuo Goto*, Kazuteru Shinozaki*, Yuriko Abe**, and Shin-ichi Ishiguro*** * Department of Chemistry, Yokohama City University, Seto, Kanazawa-ku, Yokohama 236, Japan ** Department of Chemistry, Faculty of Science, Nara Women's University, Kita-uoya-nishi-machi, Nara 630, Japan *** Department of Chemistry, Faculty of Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812, Japan Z. Naturforsch. 50a, 301-306 (1995); received September 28, 1995 Dedicated to Prof. Hitoshi Ohtaki on the occasion of his 60th birthdayThe solvation structure of Co2+ in N,N-dimethylformamide (DMF) has been studied by X-ray diffraction measurements on cobalt (II) and magnesium (II) Perchlorate solutions of the same concen tration, using an isostructural substitution method. The radial distribution function revealed three distinct peaks assigned to the oxygen, amido carbon (CJ, and nitrogen atoms of six planar DMF molecules in the first coordination sphere around the metal atom. The distance from the cobalt atom to each atom (O, Cx, N) is 213,299, and 423 pm, respectively. This indicates that the Co-O-Cj bond angle is 122-123° and the metal atom is close to the O-Cj-N plane of the DMF molecule.

show abstract

Coordination around thorium(IV) in aqueous perchlorate, chloride and nitrate solutions

1991

View full text Add to dashboard Cite

Structures of Nitrate Complexes of Erbium in Aqueous Solutions.

Cited by 23 publications

References 0 publications

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

X-Ray Diffraction Study of the Solvation Structure of the Cobalt(II) Ion in N,N-Dimethylformamide Solution

Coordination around thorium(IV) in aqueous perchlorate, chloride and nitrate solutions

Contact Info

Product

Resources

About

Structures of Nitrate Complexes of Erbium in Aqueous Solutions.

Cited by 23 publications

References 0 publications

139La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

139La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

X-Ray Diffraction Study of the Solvation Structure of the Cobalt(II) Ion in N,N-Dimethylformamide Solution

Coordination around thorium(IV) in aqueous perchlorate, chloride and nitrate solutions

Contact Info

Product

Resources

About

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions

¹³⁹La NMR Relaxation and Chemical Shift Studies in the Aqueous Nitrate and Chloride Solutions