scholarly journals Complexes of light lanthanides with 2,4-dimethoxybenzoic acid

2000 ◽  
Vol 65 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Wieslawa Ferenc ◽  
Agnieszka Walków-Dziewulska
Keyword(s):  
Ir Spectroscopy ◽  
Intermediate Formation ◽  
Carboxylate Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
One Step ◽  
Light Lanthanides ◽  
Thermogravimetric Studies ◽  
Hydrated Complexes ◽  
Two Stages

The complexes of light lanthanides with 2,4-dimethoxybenzoic acid of the formula: Ln(C9H9O4)3.nH2O where Ln = La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(IIII), and n = 3 for La(III), Gd(III), n = 2 for Sm(III), Eu(III), and n = 0 for Ce(III), Pr(III), Nd(III) have been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric studies and X-ray diffraction measurements. The complexes have colours typical for Ln 3+ ions (La, Ce, Eu, Gd-white, Sm-cream, Pr-green, Nd-violet). The carboxylate group in these complexes is a symmetrical, bidentate, chelating ligand. They are crystalline compounds characterized by various symmetry. On heating in air to 1273 K the 2,4-dimethoxybenzoates of the light lanthanides decompose in various ways. The hydrated complexes decompose in two or three steps while those of anhydrous ones only in one or two. The trihydrate of lanthanum 2,4-dimethoxybenzoate first dehydrates to form the anhydrous salt, which then decomposes to La2O3 via the intermediate formation of La2O2CO3. The hydrates of Sm(III), Eu(III), Gd(III) decompose in two stages. First, they dehydrate forming the anhydrous salts, which then decompose directly to the oxides of the respective metals. The anhydrous complexes of Ce(III), Pr(III) decompose in one step, while that of Nd(III) in two. The solubilities of the 2,4-dimethoxybenzoates of the light lanthanides in water and ethanol at 293 K are in the order of: 10 -3 mol dm -3 and 10 -4.10 -3 mol dm-3, respectively.

scholarly journals Complexes of light lanthanides with 2,3-dimethoxybenzoic acid

2001 ◽  
Vol 66 (8) ◽  
pp. 543-553 ◽  
Author(s):  
Wieslawa Ferenc ◽  
Agnieszka Walków-Dziewulska
Keyword(s):  
Ir Spectroscopy ◽  
Elemental Analysis ◽  
Magnetic Measurements ◽  
Magnetic Moments ◽  
Intermediate Formation ◽  
Carboxylate Group ◽  
X Ray ◽  
Light Lanthanides ◽  
Thermogravimetric Studies ◽  
Low Symmetry

The complexes of light lanthanides with 2,3-dimethoxybenzoic acid of the formula: Ln(C9H9O4)3, where Ln = La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III) and Gd(III) have been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric studies, as well as X-ray and magnetic measurements. The complexes have colours typical for Ln3+ ions (La, Ce, Eu, Gd-white, Sm-cream, Pr-green, Nd-violet). The carboxylate group in these complexes is a bidentate, chelating ligand or a tridentate chelating and bridging one. They are crystalline compounds characterized by low symmetry. On heating in air to 1173 K, the 2,3-dimethoxybenzoates of the light lanthanides decompose in various ways. The complexes of Ce(III), Pr(III), Sm(III), Eu(III) and Gd(III) decompose directly to oxides of the respective metals while those of La(III) and Nd(III) via the intermediate formation of La2O2CO3 and Nd2O2CO3. The solubilities of the 2,3-dimethoxybenzoates of the light lanthanides in water at 293Kare in the orders of 10-3-10-2 mol dm-3. The magnetic moments were determined in the range 4.2-298 K and the complexes are found to obey the Curie-Weiss law.

Complexes of Light Lanthanides with 3,4-Dimethoxybenzoic Acid

2000 ◽  
Vol 65 (2) ◽  
pp. 179-191 ◽  
Author(s):  
Wiesława Ferenc ◽  
Agnieszka Walków-Dziewulska
Keyword(s):  
Magnetic Moments ◽  
Intermediate Formation ◽  
Lanthanide Ions ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
X Ray ◽  
Light Lanthanides ◽  
Polycrystalline Solids ◽  
Van Vleck

The complexes of light lanthanides with 3,4-dimethoxybenzoic acid, Ln(C9H9O4)3·4 H2O, where Ln = La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III) and Gd(III), have been synthesized as polycrystalline solids and characterized by elemental analysis, IR spectroscopy, thermogravimetric and magnetic studies and X-ray diffraction measurements. The complexes possess colours typical of Ln(III) ions (La, Ce, Eu, Gd white, Pr greenish, Nd violet and Sm cream). The carboxylate group in these complexes binds as a symmetrical, bidentate chelating ligand. On heating in air to 1 273 K the 3,4-dimethoxybenzoates of Ce(III), Pr(III), Sm(III), Eu(III) and Gd(III) first dehydrate to anhydrous salts that further decompose to oxides of the respective metals. The 3,4-dimethoxybenzoates of La(III) and Nd(III) decompose in three steps. Firstly, they dehydrate to anhydrous salts that further decompose to the oxides with the intermediate formation of oxycarbonates. The solubilities of the studied complexes in water at 293 K is in the order of 10-4-10-3 mol dm-3. Their magnetic moments were determined in the temperature range 77-298 K and found to obey the Curie-Weiss law. The values of μeff calculated for the all compounds (except that for Eu) are close to those obtained for Ln(III) by Hund and van Vleck. The results show that there is no influence of the ligand field on 4f electrons of the lanthanide ions in these polycrystalline compounds; 4f electrons probably do not participate in the formation of the Ln-O bonds.

scholarly journals Spectral and thermal behaviors of rare earth element complexes with 3,5-dimethoxybenzoic acid

2003 ◽  
Vol 68 (10) ◽  
pp. 751-763 ◽  
Author(s):  
Wieslawa Ferenc ◽  
Agnieszka Walkóv-Dziewulska ◽  
Janusz Chrusciel
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earth Element ◽  
Earth Element ◽  
Magnetic Measurements ◽  
Quantitative Composition ◽  
Carboxylate Group ◽  
X Ray ◽  
Thermogravimetric Studies ◽  
Hydrated Complexes

The conditions for the formation of rare earth element 3,5-dimethytoxybenzoates were studied and their quantitative composition and solubilities in water at 293 K were determined. The complexes are anhydrous or hydrated salts and their solubilities are of the orders of 10-5 ? 10-4 mol dm-3. Their FTIR, FIR and X-ray spectra were recorded. The compounds were also characterized by thermogravimetric studies in air and nitrogen atmospheres and by magnetic measurements. All complexes are crystalline compounds. The carboxylate group in these complexes is a bidentate chelating ligand. On heating in air to 1173 K, the 3,5-dimethoxybenzoates of rare earth elements decompose in various ways. The hydrated complexes first dehydrate to form anhydrous salts which then decompose in air to the oxides of the respective metals while in nitrogen to mixtures of carbon and oxides of the respective metals. The complexes are more stable in air than in nitrogen.

scholarly journals The physico-chemical properties of 2-methoxyphenoxyacetates of Mn(II), Co(II), Ni(II) and Cu(II)

2018 ◽  
Vol 35 (2) ◽  
pp. 89
Author(s):  
W. Ferenc ◽  
M. Bernat ◽  
J. Sarzyński
Keyword(s):  
Magnetic Moments ◽  
Chemical Properties ◽  
Intermediate Formation ◽  
Bidentate Ligands ◽  
X Ray Diffraction ◽  
Solubility In Water ◽  
Physico Chemical ◽  
One Step ◽  
Thermogravimetric Studies ◽  
Ligand Fields

The complexes of 2-methoxyhenoxyacetates of Mn(II), Co(II), Ni(II) and  Cu(II)with the general formula: M(C9H9O4)3·4H2O, where M(II) = Mn, Co, Ni and Cu have been synthesized and characterized by elemental analysis, IR spectroscopy, magnetic and thermogravimetric studies and also X-ray diffraction measurements. The complexes have colours typical for M(II) ions (Mn(II) - a pale pink, Co(II) - pink, Ni(II) - green, and Cu(II) – blue). The carboxylate group binds as monodentate and bidentate ligands. On heating to 1273K in air thecomplexes decompose in the same way. At first, they dehydrate in one step to anhydrous salts, that next decompose to the oxides of respective metals with the intermediate formation of the oxycarbonates. Their solubility in water at 293K is of the order of 10-5 mol·dm-3. The magnetic moments of analysed complexes were determined in the range of 76-303K. The results reveal them to be high-spin complexes of weak ligand fields.

scholarly journals Physicochemical properties of 3, 4, 5–trimethoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)

2005 ◽  
Vol 70 (8-9) ◽  
pp. 1075-1088 ◽  
Author(s):  
Wieslawa Ferenc ◽  
Agnieszka Walków-Dziewulska ◽  
Jan Sarzynski
Keyword(s):  
Ir Spectroscopy ◽  
Magnetic Moments ◽  
X Ray Diffraction ◽  
Acid Anion ◽  
Magnetic Studies ◽  
Bridging Ligands ◽  
Magnetic Susceptibilities ◽  
X Ray ◽  
Carboxylate Groups ◽  
One Step

The complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with 3,4,5-trimethoxybenzoic acid anion of the formula: M(C10H11O5)2.nH2O, where n = 6 for Ni(II), n = 1 for Mn(II), Co(II), Cu(II), and n = 0 for Zn, have been synthesized and characterized by elemental analysis, IR spectroscopy X?ray diffraction measurements, thermogravimetry and magnetic studies. They are crystalline compounds characterized by various symmetry. They decompose in various ways when heated in air to 1273 K. At first, they dehydrate in one step and form anhydrous salts. The final products of decomposition are oxides of the respective metals (Mn2O3, Co3O4, NiO, CuO, ZnO). The solubilities of the analysed complexes in water at 293 K are in the orders of 10-2 ? 10-4 mol dm-3. The magnetic susceptibilities of the Mn(II), Co(II), Ni(II) and Cu(II) complexes were measured over the range of 76?303 K and the magnetic moments were calculated. The results show that the 3,4,5-trimethoxybenzoates of Mn(II), Co(II) and Ni(II) are high-spin complexes but that of Cu(II) forms a dimer [Cu2(C10H11O5)4(H2O)2]. The carboxylate groups bind as monodentate or bidentate chelating or bridging ligands.

scholarly journals Magnetic, thermal and spectroscopic properties of lanthanide(III) 2-(4-chlorophenoxy) acetates, Ln(C8H6ClO3)3•nH2O

2013 ◽  
Vol 78 (9) ◽  
pp. 1335-1349 ◽  
Author(s):  
Wiesława Ferenc ◽  
Beata Cristóvão ◽  
Jan Sarzyński
Keyword(s):  
Magnetic Moments ◽  
Intermediate Formation ◽  
Spectroscopic Properties ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
Magnetic Susceptibilities ◽  
X Ray ◽  
Gaseous Products ◽  
Carboxylate Groups ◽  
Thermogravimetric Studies

4-Chlorophenoxyacetates of lanthanides(III) were synthesized as polycrystalline hydrated solids with the general formulae: Ln(C8H6ClO3)3?2H2O (Ln = La(III), Pr(III), Sm(III), Eu(III) and Tb(III)), Ln(C8H6ClO3)3?H2O (Ln = Dy(III)) and Ln(C8H6ClO3)3?3H2O (Ln = Er(III), Tm(III), Yb(III) and Lu(III) and characterized by elemental analysis, FTIR spectroscopy, magnetic and thermogravimetric studies and also by X-ray diffraction (XRD) measurements. The complexes have colours typical for lanthanide(III) ions. The carboxylate groups bind as bidentate chelating. On heating to 1273 K in air the complexes decompose in three steps. At first they dehydrate in one stage to form anhydrous salts that next decompose to the oxides of respective metals with the intermediate formation of their oxychlorides. The gaseous products of compound thermal decomposition in nitrogen were also determined and the magnetic susceptibilities were measured over the ranges 76-303K and 1.8-303K, and their magnetic moments were calculated. The results show that 4-chlorophenoxyacetates of lanthanides(III) are high-spin complexes with weak ligand field.

Hydrolytic products of Fe(III) after oxidation of Fe(II) by chlorate

1982 ◽  
Vol 47 (4) ◽  
pp. 1069-1077 ◽  
Author(s):  
Karel Mádlo ◽  
František Hanousek ◽  
Antonín Petřina ◽  
Jaroslav Tláskal
Keyword(s):  
Electron Microscopy ◽  
Ir Spectroscopy ◽  
Chemical Analysis ◽  
Ferrous Sulphate ◽  
Reaction Medium ◽  
Potassium Chlorate ◽  
X Ray Diffraction ◽  
X Ray

Ferrous sulphate was oxidized by potassium chlorate in the pH region 2-7 and at temperatures ranging from 298.1 to 323.1 K and various hydrolytic products of Fe(III) were separated and indentified. The separated solid ferric products were analyzed using a combination of the chemical analysis, IR spectroscopy, X-ray diffraction, and electron microscopy. The following substances were found as major components of the products: Fe2O3.n H2O ("ferric gel"), Fe2O3.n H2O with bound SO2-4 ions ("sulphogel"), α-FeO(OH), γ-FeO(OH) and Fe3O4. Their amount depends particularly on the pH temperature of the reaction medium.

scholarly journals High-pressure synthesis of REB5O8(OH)2 (RE = Ho, Er, Tm)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Michael Zoller ◽  
Hubert Huppertz
Keyword(s):  
High Pressure ◽  
Rare Earth ◽  
Ir Spectroscopy ◽  
Earth Metal ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Solution ◽  
Pressure Synthesis ◽  
The Rare Earth

AbstractThe rare earth oxoborates REB5O8(OH)2 (RE = Ho, Er, Tm) were synthesized in a Walker-type multianvil apparatus at a pressure of 2.5 GPa and a temperature of 673 K. Single-crystal X-ray diffraction data provided the basis for the structure solution and refinement. The compounds crystallize in the monoclinic space group C2 (no. 5) and are composed of a layer-like structure containing dreier and sechser rings of corner sharing [BO4]5− tetrahedra. The rare earth metal cations are coordinated between two adjacent sechser rings. Further characterization was performed utilizing IR spectroscopy.

scholarly journals Exploring the Structural Chemistry of Pyrophosphoramides: N,N′,N″,N‴-Tetraisopropylpyrophosphoramide

Chemistry ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 149-163
Author(s):  
Duncan Micallef ◽  
Liana Vella-Zarb ◽  
Ulrich Baisch
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Hydrogen Bonding ◽  
Nmr Spectroscopy ◽  
Ir Spectroscopy ◽  
Room Temperature ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray

N,N′,N″,N‴-Tetraisopropylpyrophosphoramide 1 is a pyrophosphoramide with documented butyrylcholinesterase inhibition, a property shared with the more widely studied octamethylphosphoramide (Schradan). Unlike Schradan, 1 is a solid at room temperature making it one of a few known pyrophosphoramide solids. The crystal structure of 1 was determined by single-crystal X-ray diffraction and compared with that of other previously described solid pyrophosphoramides. The pyrophosphoramide discussed in this study was synthesised by reacting iso-propyl amine with pyrophosphoryl tetrachloride under anhydrous conditions. A unique supramolecular motif was observed when compared with previously published pyrophosphoramide structures having two different intermolecular hydrogen bonding synthons. Furthermore, the potential of a wider variety of supramolecular structures in which similar pyrophosphoramides can crystallise was recognised. Proton (1H) and Phosphorus 31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS) were carried out to complete the analysis of the compound.

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