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Title: Crystal chemistry of M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds (M=Mg, Mn, Fe, Co, Ni, Zn, Cd): Structural investigation of the Ni, Zn and Cd salts

Abstract

The compounds M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O (M=Mg, Mn, Fe, Co, Ni, Zn, Cd) were prepared from super-saturated aqueous solutions at room temperature. Single-crystal X-ray structure investigations of members with M=Ni, Zn, Cd were performed at 295 and 120 K. The space-group symmetry is P2{sub 1}/n, Z=2. The unit-cell parameters are at 295/120 K for M=Ni: a=7.240(2)/7.202(2), b=9.794(2)/9.799(2), c=5.313(1)/5.285(1) A, {beta}=94.81(1)/94.38(1){sup o}, V=375.4/371.9 A{sup 3}; M=Zn: a=7.263(2)/7.221(2), b=9.893(2)/9.899(3), c=5.328(1)/5.296(2) A, {beta}=94.79(1)/94.31(2){sup o}, V=381.5/377.5 A{sup 3}; M=Cd: a=7.356(2)/7.319(2), b=10.416(2)/10.423(3), c=5.407(1)/5.371(2) A, {beta}=93.85(1)/93.30(2){sup o}, V=413.4/409.1 A{sup 3}. Layers of corner-shared MO{sub 6} octahedra and phosphate tetrahedra are linked by three of the four crystallographically different hydrogen bonds. The fourth hydrogen bond (located within the layer) is worth mentioning because of the short O{sub h}...O bond distance of 2.57-2.61 A at room temperature (2.56-2.57 A at 120 K); only for M=Mg it is increased to 2.65 A. Any marked temperature-dependent variation of the unit-cell dimension is observed only vertical to the layers. The analysis of the infrared (IR) spectroscopy data evidences that the internal PO{sub 4} vibrations are insensitive to the size and the electronic configuration of the M {sup 2+} ions. The slight strengthening of the intra-molecular P-O bonds in the Mgmore » salt is caused by the more ionic character of the Mg-O bonds. All IR spectra exhibit the characteristic 'ABC trio' for acidic salts: 2900-3180 cm{sup -1} (A band), 2000-2450 cm{sup -1} (B band) and 1550-1750 cm{sup -1} (C band). Both the frequency and the intensity of the A band provide an evidence that the PO{sub 2}(OH){sub 2} groups in M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds form weaker hydrogen bonds as compared with other acidic salts with comparable O...O bond distances of about 2.60 A. The observed shift of the O-H stretching vibrations of the water molecule in the order M=Mg>Mn{approx}Fe{approx}Co>Ni>Zn{approx}Cd has been discussed with respect to the influence of both the character and the strength of M{r_reversible}H{sub 2}O interactions. - Graphical abstract: IR spectroscopy showed the internal PO{sub 4} vibrations to be insensitive to the size and the electronic configuration of the M {sup 2+} ions and reflect the more ionic character of the Mg-O bonds. The observed 'ABC trio' characteristic for acidic salts is discussed. Single-crystal X-ray investigations were performed at 120 and 295 K. One of the four hydrogen bonds is worth mentioning because of the short O{sub h}...O bond distance of 2.57-2.61 A at room temperature (2.56-2.57 A at 120 K)« less

Authors:
 [1];  [2]
  1. Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bl.11, 1113 Sofia (Bulgaria), E-mail: vkoleva@svr.igic.bas.bg
  2. Institut fuer Mineralogie und Kristallographie, Universitaet Wien, Althanstrasse 14, A-1090 Vienna (Austria), E-mail: herta.silvia.effenberger@univie.ac.at
Publication Date:
OSTI Identifier:
21015734
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2006.12.024; PII: S0022-4596(07)00003-5; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BOND LENGTHS; CADMIUM COMPOUNDS; COBALT COMPOUNDS; ELECTRONIC STRUCTURE; INFRARED SPECTRA; IONS; IRON COMPOUNDS; LATTICE PARAMETERS; LAYERS; MAGNESIUM COMPOUNDS; MANGANESE COMPOUNDS; MONOCLINIC LATTICES; MONOCRYSTALS; NICKEL COMPOUNDS; PHOSPHATES; SPACE GROUPS; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; ZINC COMPOUNDS

Citation Formats

Koleva, Violeta, and Effenberger, Herta. Crystal chemistry of M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds (M=Mg, Mn, Fe, Co, Ni, Zn, Cd): Structural investigation of the Ni, Zn and Cd salts. United States: N. p., 2007. Web. doi:10.1016/j.jssc.2006.12.024.
Koleva, Violeta, & Effenberger, Herta. Crystal chemistry of M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds (M=Mg, Mn, Fe, Co, Ni, Zn, Cd): Structural investigation of the Ni, Zn and Cd salts. United States. doi:10.1016/j.jssc.2006.12.024.
Koleva, Violeta, and Effenberger, Herta. Thu . "Crystal chemistry of M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds (M=Mg, Mn, Fe, Co, Ni, Zn, Cd): Structural investigation of the Ni, Zn and Cd salts". United States. doi:10.1016/j.jssc.2006.12.024.
@article{osti_21015734,
title = {Crystal chemistry of M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds (M=Mg, Mn, Fe, Co, Ni, Zn, Cd): Structural investigation of the Ni, Zn and Cd salts},
author = {Koleva, Violeta and Effenberger, Herta},
abstractNote = {The compounds M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O (M=Mg, Mn, Fe, Co, Ni, Zn, Cd) were prepared from super-saturated aqueous solutions at room temperature. Single-crystal X-ray structure investigations of members with M=Ni, Zn, Cd were performed at 295 and 120 K. The space-group symmetry is P2{sub 1}/n, Z=2. The unit-cell parameters are at 295/120 K for M=Ni: a=7.240(2)/7.202(2), b=9.794(2)/9.799(2), c=5.313(1)/5.285(1) A, {beta}=94.81(1)/94.38(1){sup o}, V=375.4/371.9 A{sup 3}; M=Zn: a=7.263(2)/7.221(2), b=9.893(2)/9.899(3), c=5.328(1)/5.296(2) A, {beta}=94.79(1)/94.31(2){sup o}, V=381.5/377.5 A{sup 3}; M=Cd: a=7.356(2)/7.319(2), b=10.416(2)/10.423(3), c=5.407(1)/5.371(2) A, {beta}=93.85(1)/93.30(2){sup o}, V=413.4/409.1 A{sup 3}. Layers of corner-shared MO{sub 6} octahedra and phosphate tetrahedra are linked by three of the four crystallographically different hydrogen bonds. The fourth hydrogen bond (located within the layer) is worth mentioning because of the short O{sub h}...O bond distance of 2.57-2.61 A at room temperature (2.56-2.57 A at 120 K); only for M=Mg it is increased to 2.65 A. Any marked temperature-dependent variation of the unit-cell dimension is observed only vertical to the layers. The analysis of the infrared (IR) spectroscopy data evidences that the internal PO{sub 4} vibrations are insensitive to the size and the electronic configuration of the M {sup 2+} ions. The slight strengthening of the intra-molecular P-O bonds in the Mg salt is caused by the more ionic character of the Mg-O bonds. All IR spectra exhibit the characteristic 'ABC trio' for acidic salts: 2900-3180 cm{sup -1} (A band), 2000-2450 cm{sup -1} (B band) and 1550-1750 cm{sup -1} (C band). Both the frequency and the intensity of the A band provide an evidence that the PO{sub 2}(OH){sub 2} groups in M[PO{sub 2}(OH){sub 2}]{sub 2}.2H{sub 2}O compounds form weaker hydrogen bonds as compared with other acidic salts with comparable O...O bond distances of about 2.60 A. The observed shift of the O-H stretching vibrations of the water molecule in the order M=Mg>Mn{approx}Fe{approx}Co>Ni>Zn{approx}Cd has been discussed with respect to the influence of both the character and the strength of M{r_reversible}H{sub 2}O interactions. - Graphical abstract: IR spectroscopy showed the internal PO{sub 4} vibrations to be insensitive to the size and the electronic configuration of the M {sup 2+} ions and reflect the more ionic character of the Mg-O bonds. The observed 'ABC trio' characteristic for acidic salts is discussed. Single-crystal X-ray investigations were performed at 120 and 295 K. One of the four hydrogen bonds is worth mentioning because of the short O{sub h}...O bond distance of 2.57-2.61 A at room temperature (2.56-2.57 A at 120 K)},
doi = {10.1016/j.jssc.2006.12.024},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 180,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
  • Compounds of the Na{sub 1.5}(Mn{sub 1-x}M{sub x}{sup 2+}){sub 1.5}Fe{sub 1.5}(PO{sub 4}){sub 3} (M{sup 2+}=Cd{sup 2+}, Zn{sup 2+}) alluaudite-type solid solutions were synthesized by solid-state reactions in air, between 800 and 900 deg. C, and were investigated by X-ray powder diffraction and infrared spectroscopy. The site occupancy factors of the Na{sub 1.5}(Mn{sub 1-x}Cd{sub x}{sup 2+}){sub 1.5}Fe{sub 1.5}(PO{sub 4}){sub 3} compounds, obtained from the Rietveld refinements of the X-ray powder patterns, indicate that the replacement of Mn{sup 2+} by Cd{sup 2+} takes place on the M(1) site for x=0.25 and 0.50, and then on the M(1) and M(2) sites for x=0.75 andmore » 1.00. Small amounts of Cd{sup 2+} were also detected on the A(1) site, compensated by small amounts of Na{sup +} occurring on M(1). This partially disordered distribution is probably due to the similar effective ionic radii of Cd{sup 2+} and Na{sup +}. The cationic distributions in the Na{sub 1.5}(Mn{sub 1-x}Zn{sub x}{sup 2+}){sub 1.5}Fe{sub 1.5}(PO{sub 4}){sub 3} solid solution indicate that Zn{sup 2+} was first introduced in the M(2) site, before to replace Mn{sup 2+} in the M(1) site. The unit-cell parameters show a significant increase when Mn{sup 2+} is replaced by Cd{sup 2+}, and a significant decrease when it is replaced by Zn{sup 2+}. The variations of the {beta} angle were also correlated with the M(1)-M(2) distances. The infrared spectra show the displacement of an absorption band at ca. 400-425 cm{sup -1}, which is assigned to the vibrations of the M{sup 2+} cations localized on the M(1) site. This assignment is confirmed by the excellent correlations between the M(1)-O bond distances and the energy of the absorption band. - Graphical abstract: The crystal structure of Na{sub 1.5}Zn{sub 1.5}Fe{sup 3+}{sub 1.5}(PO{sub 4}){sub 3}.« less
  • A series of metalloborophosphates Na{sub 2}[M {sup II}B{sub 3}P{sub 2}O{sub 11}(OH)].0.67H{sub 2}O (M {sup II}=Mg, Mn, Fe, Co, Ni, Cu, Zn) have been prepared hydrothermally and their structures have been solved by single-crystal diffraction techniques. They all crystallize in a hexagonal space group P6{sub 3} and form a 3D microporous structure with 12-membered ring channels consisted of octahedral (M {sup II}O{sub 6}), tetrahedral (BO{sub 4}, PO{sub 4}) and triangular (BO{sub 2}(OH)) units, in which the counter Na{sup +} cations and water molecules are located. The Na{sup +} cations are mobile and can be exchanged by Li{sup +} in a meltmore » of LiNO{sub 3}. Their open frameworks are thermal stable up to about 500 deg. C. Completed solid solutions between two different transition metals can also be obtained. Magnetic properties of Na{sub 2}[M {sup II}B{sub 3}P{sub 2}O{sub 11}(OH)].0.67H{sub 2}O (M {sup II}=Mn, Co, Ni, Cu) have been investigated. - Graphical abstract: A series of metalloborophosphates Na{sub 2}[M {sup II}B{sub 3}P{sub 2}O{sub 11}(OH)].0.67H{sub 2}O (M {sup II}=Mg, Mn, Fe, Co, Ni, Cu, Zn) were synthesized under hydrothermal conditions (473 K). The structure consists of microporous 3D open framework with 12-membered ring channels composed of octahedral (M {sup II}O{sub 6}), tetrahedral (BO{sub 4}, PO{sub 4}) and triangular (BO{sub 2}(OH)) units.« less
  • The representatives of the new isotypic series M{sub 3}Fe{sub 2}(SeO{sub 3}){sub 6}{center_dot} 2H{sub 2}O (M = Mg, Co, Ni) were prepared at 500 K from aqueous solutions, kept in Teflon-coated autoclaves. Their crystal structures were determined by direct methods from single-crystal X-ray diffraction data in the space group P{bar 1} with Z = 1. Mg{sub 3}Fe{sub 2}(SeO{sub 3}){sub 6} {center_dot} 2H{sub 2}O: a = 6.494(2), b = 7.959(3), c = 8.810(4) {angstrom}, {alpha} = 85.88(2), {beta} = 79.12(2), {gamma} = 76.09(2){degrees}, V = 433.9 {angstrom}{sup 3}. Co{sub 3}Fe{sub 2} (SeO{sub 3}){sub 6} {center_dot} 2H{sub 2}O: a = 6.520(2), b =more » 7.995(3), c = 8.774(4) {angstrom}, {alpha} = 85.51(2), {beta} = 78.77(1), {gamma} = 75.84(1){degrees}, V = 434.8 {angstrom}{sup 3}. Ni{sub 3}Fe{sub 2} (SeO{sub 3}){sub 6} {center_dot} 2H{sub 2}O: a = 6.474(2), b = 7.943(3), c = 8.736(4) {angstrom}, {alpha} = 85.37(1), {beta} = 78.51(1), {gamma} = 75.91(1){degrees}, V = 426.7 {angstrom}{sup 3}. The three different M sites are commonly occupied by M{sup 2+} and Fe{sup 3+} atoms in varying ratios. MO{sub 6} octahedra are linked to each other by edges to build four-membered groups. Via common corners with further MO{sub 6} octahedra and trigonal pyramidal SeO{sub 3} groups, complex sheets parallel to (001) are formed which are interconnected by hydrogen bonds only. IR and Moessbauer spectra are discussed.« less