Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. IX. Some Complexes of Group 2 Metal Halides With 2,2':6',2"-Terpyridine

1996 ◽  
Vol 49 (1) ◽  
pp. 137 ◽  
Author(s):  
BW Skelton ◽  
AF Waters ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Nitrogen Base ◽  
Space Group ◽  
Trigonal Symmetry ◽  
X Ray ◽  
Space Groups ◽  
Structure Determinations ◽  
Group 2 ◽  
A Site

Syntheses and room-temperature single-crystal X-ray structure determinations are recorded for a number of adducts of MX2.ntpy stoichiometry of salts of Group 2 metals, MX2, with 2,2':6',2"-terpyridine ( tpy ). ' Homoleptic' adducts, [M( tpy )3] X2, are found in space groups with trigonal symmetry, with M located on a site of at least 3 symmetry, the structures being derivative of the P 62c array found in [ Pb ( tpy )3] (ClO4)2, but with variations in anion and cation stackings . [M( tpy )3] I2.~1.7MeOH, M = Ca (1), Sr (2), are trigonal , P3c1, a ≈ 13, c ≈ 15.3 Ǻ, Z = 2 f.u., conventional R on ׀ F ׀ being 0.050, 0.086 for No 894, 865 independent 'observed' (I > 3σ(I)) reflections respectively. [ Sr ( tpy )3] Br2.2MeOH (3), although similar, is modelled in space group P3c1, a 13.040(4), c 15.13(1) Ǻ, Z = 2 f.u ., R 0.041 for No 447. [( tpy )2BaI2] (4) is monoclinic, P 21/c, a 10.812(4), b 16.740(5), c 17.458(4) Ǻ, β 109.39(2)°, Z = 4 f.u ., R 0.042 for No 3256. [( tpy )2Ba(O2ClO2)2] (5) is triclinic, Pī , a 14.220(4), b 11.212(2), c 10.511(2) Ǻ, α 65.66(2), β 87.32(2), γ 88.92(2)°, Z = 2 f.u ., R 0.029 for No 4676.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. V. Some Complexes With 3-Azapentane-1,5-diamine

1996 ◽  
Vol 49 (1) ◽  
pp. 73 ◽  
Author(s):  
AF Waters ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Tridentate Ligands ◽  
Nitrogen Base ◽  
Space Group ◽  
X Ray ◽  
Group 2 ◽  
Probable Space ◽  
Structural Characterizations

Syntheses and room-temperature single-crystal X-ray structural characterizations are recorded for an array of adducts of H2N(CN2)2NH(CH2)2NH2, ' dien ', with salts of Group 2 elements, MX2.n( dien ).[Mg( dien )2] Cl2 (1) is monoclinic, P 21/c, a 11.326(6), b 10.928(5), c 12.636(6) Ǻ, β 92.74(4)°, Z = 4 f.u .; R was 0.047 for No 1726 independent 'observed' (I > 3σ(I)) diffractometer reflections. [Mg( dien )2] Br2 (2) is monoclinic, P 21/c, a 9.541(7), b 14.55(1), c 11.894(8) Ǻ, β 100.42(5)°, Z = 4 f.u ., R 0.054 for No 1778. [Mg( dien )2] I2 (3) is isomorphous , a 9.969(2), b 14.907(2), c 12.300(3) Ǻ, β 100.02(2)°, R 0.039 for No 3180. In all three complexes, the two tridentate ligands are disposed mer in a six-coordinate MgN6 environment, the trans Mg-N(central) distances being somewhat shorter (2.161 (4)-2.181(9)Ǻ) than Mg-N(distal) (2.215(8)-2.249(4)Ǻ). [Ba(dien)3] Cl2 (4a) is orthorhombic, Pnaa , a 19.309(2), b 13.545(2), c 8.872(2)Ǻ, Z = 4 f.u ., R 0.055 for No 1070; the methanol disolvate (4b) is monoclinic, P 21/c, a 16.807(8), b 8.764(5), c 19.493(4) Ǻ, β 102.39(3)°, Z = 4 f.u ., R 0.11 for No 2613. A family of derivative structures (5)-(8), [M( dien )3] X2, M, X = Sr , Br (5), Sr , I(6), Ba , Br (7), Ba , I(8), have cells of half the volume (a ≈ 13.8, b ≈ 9, c ≈ 9.8 Ǻ), probable space group P21212, R 0.050, 0.061, 0.034, 0.037 for No 549, 914, 1044, 1801 respectively, with the cations disposed about crystallographic 2 axes with one disordered ligand . [ Ba( dien )3](ClO4)2 (9) is rhombohedral , R3c, a 10.240(2), c 45.19(1) Ǻ (hexagonal setting), Z = 6 f.u ., R 0.054 for No 508. Like (4)-(8), the barium environment is nine-coordinate with the three tridentate ligands here� disposed about a 3 axis through the metal.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. IV. Some Complexes of Group 2 Halides With Ethane-1,2-diamine

1996 ◽  
Vol 49 (1) ◽  
pp. 61 ◽  
Author(s):  
AF Waters ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Metal Salts ◽  
Nitrogen Base ◽  
X Ray ◽  
Structure Determinations ◽  
Group 2

Syntheses and room-temperature single-crystal X-ray structure determinations are recorded for a number of adducts of ethane-1,2-diamine (en) with Group 2 metal salts, MX2.n(en). [Mg(en)3] Br2.MeOH (1) is monoclinic, P 21/c, a 9.067(5), b 15.161(4), c 14.839(8) Ǻ, β 121.86(5)°, Z = 4 f.u .; R was 0.070 for No 1226 independent 'observed' (I > 3σ(I)) diffractometer reflections; [Mg(en)3] I2.MeOH (2) is triclinic, Pī , a 11.500(2), b 9.527(6), c 8.825(4) Ǻ, α 106.30(4), β 100.57(3), γ 90.28(4)°, Z = 2 f.u .; R 0.045 for No 3562. In (1) and (2), (Mg-N) are 2.20 and 2.19 Ǻ. [Ca(en)4]Br2 (3) is orthorhombic, Fddd , a 28.54(1), b 15.863(7), c 8.927(9) Ǻ, Z = 8 f.u .; Ca-N are 2.608(7) and 2.556(8) Ǻ. [ Sr (en)4] Cl2.2MeOH (4) is also orthorhombic, Fddd , a 26.627(8), b 15.388(4), c 11.313(4) Ǻ, Z = 8 f.u .; R 0.059 for No 535. [ Sr (en)4] Br2.2en (5) is tetragonal, I 41/a, a 9.215(7), c 27.678(3) Ǻ, Z = 4 f.u ., R 0.044 for No 657. [ Sr (en)4]I2.MeOH (6) is tetragonal, I41/amd, a 9.389(1), c 28.78(1) Ǻ, Z = 4. f.u ., R 0.040 for No 10. In (4), (5) and (6), Sr -N are 2.728(7), 2.718(7); 2.720(7), 2.703(7) and 2.75(2), 2.72(7) Ǻ. [ ClBa (en)3(en)(2/2)](∞ ׀ ∞) Cl (≡ BaCl2.4en) (7) is monoclinic, P 21, a 8.666(3), b 9.063(10), c 12.655(5) Ǻ, β 108.13(3)°, Z = 2 f.u ., R 0.048 for No 1479. In (1) and (2), magnesium is six-coordinate [Mg(N,N'- bidentate )3]; (3)-(6), calcium and strontium are eight-coordinate [M(N,N'- bidentate )4]; in (7), barium is nine-coordinate, one of the en ligands being bridging so that the complex is a single-stranded polymer generated by the 21 screw. Ba-Cl is 3.419(5) Ǻ, Ba -N bidentate en-N are 2.91(2)-2.97(3) Ǻ, and Ba -N monodentate en-N 2.92(1), 3.15(1) Ǻ.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. VI. Mixed Oligodentate-Aliphatic-Base/Oxygen Ligand Adducts

1996 ◽  
Vol 49 (1) ◽  
pp. 87 ◽  
Author(s):  
AF Waters ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Mixed Ligand ◽  
Metal Salts ◽  
Precise Description ◽  
Nitrogen Base ◽  
X Ray ◽  
Oxygen Ligand ◽  
Group 2 ◽  
Ligand Species

In the course of synthesizing oligodentate aliphatic nitrogen base adducts of Group 2 metal salts, a number of mixed- ligand species have been isolated with oxygen ligands , and characterized by room-temperature single-crystal X-ray studies. BaCl2.4en.H2O ≡[(en)4Ba(OH2)] Cl2 (1) is monoclinic, P 21/c, a 9.456(4), b 14.953(6), c 14.82(1) Ǻ, β 100.78(6)°, Z = 4 f.u ., R 0.043 for No 1862 independent 'observed' (I > 3σ(I)) diffractometer reflections. Ba -N range between 2.900(9) and 2.97(1) Ǻ, and Ba-O is 2.779(8) Ǻ in the nine-coordinate BaN8O environment. CaCl2.2dien.H2O ≡ [( dien )2Ca(OH2) Cl ] Cl (2) is monoclinic, P 21/c, a 10.808(4), b 11.999(4), c 15.71(1) Ǻ, β 123.58(4)°, Z = 4 f.u ., R 0.050 for No 3134; CaBr2.2dien.2H2O ≡ [( dien )2Ca(OH2)2] Br2 (3) is monoclinic, P 21/c, a 18.001(3), b 11.983(6), c 21.562(5) Ǻ, β 124.97(2)°, Z = 8 f.u ., R 0.045 for No 2858; CaBr2.2dien.2MeOH ≡ [( dien )2Ca( HOMe )2] Br2 (4) is orthorhombic, P212121, a 16.620(8), b 12.78(1), c 9.765(4) Ǻ, Z = 4 f.u ., R 0.073 for No 878. In (2)-(4), the cation configurations are similar, being of the form [L2Ca( dien )2], L (L') being the unidentate ligand, with the eight-coordinate calcium environments [L2Ca(N3)2] in a common isomeric configuration, the two ligands L being cis in an array of quasi-2 symmetry. Ca- Cl in (2) is 2.834(1) Ǻ; Ca-N generally range between 2.52(5) and 2.64(1) Ǻ; Ca-O(H2O) is 2.418(2) in (2), 2.434(7)-2.496(7) Ǻ in (3), while Ca-O( MeOH ) in (4) are 2.43(2) and 2.43(2) Ǻ. [Mg(HOMe)6] I2.2tmeda (5) ( tmeda = Me2N(CH2)2NMe2), orthorhombic, Pbca, a 23.423(8), b 15.306(4), c 9.345(1) Ǻ, Z = 4 f.u ., R 0.052 for No 1928, provides a usefully precise description for the centrosymmetric cation, Mg-O being 2.069(4), 2.080(4), 2.096(5) Ǻ, with Mg-O-C 128.4(4) l28.9(4), l29.7(4)°. [( tmeda )SrI2 ( HOMe )3].½tmeda (6), monoclinic, P 21/c, a 7.730(1), b 35.493(9), c 11.081(2) Ǻ, β 126.49(1)°, R 0.042 for No 3161, has a seven-coordinate, quasi-pentagonal bipyramidal SrN2I2O3 array about the metal with trans-iodines.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. II. Some Adducts of Group 2 Salts With Pyridine

1996 ◽  
Vol 49 (1) ◽  
pp. 35 ◽  
Author(s):  
AF Waters ◽  
AH White
Keyword(s):  
Metal Atom ◽  
Room Temperature ◽  
Site Symmetry ◽  
Nitrogen Base ◽  
Coordination Environment ◽  
X Ray ◽  
Pyridine Nitrogen ◽  
The Subject ◽  
Group 2 ◽  
A Site

Recrystallization of Group 2 halides from pyridine ( py ) solution has yielded, in a number of cases, crystalline adducts MX2.npy which have been the subject of room-temperature single-crystal X-ray structural characterization. MgBr2.6py (1) is orthorhombic, Ccca, a 11.575(2), b 14.999(4), c 17.292(2) Ǻ, Z = 4; conventional R on [F] for No = 752 'observed' (I > 3σ(I)) reflections was 0.043. The compound is formulated as [( py )4MgBr2].2py, the metal atom on a site of 222 symmetry having a trans-X2MN4 coordination environment. With CaCl2, a 1:2 adduct (2) is formed, orthorhombic, Fdd2, a 33.83(1), b 18.143(2), c 3.981(7) Ǻ, Z = 8 f.u ., R 0.040 for No 451; the complex is an infinite polymer along c, [( py )2CaCl2](∞ ׀ ∞), the…CaCl2CaCl2Ca…spine having six-coordinate, octahedral calcium environments in which the pyridine nitrogen atoms are bound trans to either side, with the calcium site symmetry being 2. With SrBr2, a 1:5 adduct (3) is found, mononuclear, [( py )5SrBr2], with the metal atom in a pentagonal bipyramidal coordination environment (orthorhombic, Pcab , a 18.611(5), b 17.768(7), c 17.411(7) Ǻ, Z = 8; R 0.060 for No 949). With BaI2, a 1:6 adduct (4) is obtained, [( py )6BaI2], the eight-coordinate barium atom lying on a crystallographic 2 axis in a monoclinic C2/c cell, Z = 4, a 18.311(2), b 9.960(3), c l8.856(8) Ǻ, β 99.28(3)° (R 0.031 for No 2279), with the iodide atoms occupying a pair of B sites in one of the trapezoidal planes of a quasi-dodecahedral array. [(2-mpy)2MgBr2] (5), 2-mpy=2-methylpyridine, is of interest, offering a four-coordinate N2MgBr2 array (triclinic, Pī, a 8.046(3), b 8.873(3), c 11.475(1) Ǻ, α 86.25(2), β 78.82(5), γ 67.88(5)°, Z = 2; R 0.069 for No 2091), while [( py )6/(4-mpy)6Ba(O2ClO2)2] (6) and (7), perhaps surprisingly, are isomorphous with (4), with O,O'-bidentate perchlorates replacing iodide in the coordination sphere (R 0.031 and 0.052 for No 2401 and 2204 respectively). With 3,5-dmpy (3,5-dimethylpyridine), strontium iodide yields a trans-six- rather than seven-coordinate adduct, [(3,5-dmpy)4SrI2] (8), the molecule conforming to crystallographic 4/m symmetry in the tetragonal space group I4/m, a 9.808(4), c 17.196(8) Ǻ, Z = 2; R 0.066 for No 608.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. I. Some Adducts of Group 2 Halides With Acetonitrile

1996 ◽  
Vol 49 (1) ◽  
pp. 27 ◽  
Author(s):  
AF Waters ◽  
AH White
Keyword(s):  
Coordination Sphere ◽  
Molecular Species ◽  
Room Temperature ◽  
Linear Array ◽  
Nitrogen Base ◽  
X Ray ◽  
Unusual Combination ◽  
Anionic Species ◽  
Group 2 ◽  
O 352

Recrystallization of anhydrous Group 2 halides from anhydrous acetonitrile has yielded, in a number of cases, adducts MX2.nMeCN suitable for characterization by room-temperature single-crystal X-ray studies, which revealed novel stereochemical types. Magnesium(II) bromide yields a trisolvate, ionic with disproportionated ligand arrays, as [Mg(NCMe)6][MgBr4] (1), an unusual combination of homoleptic cationic and anionic species. Crystals are triclinic, Pī , a 19.129(1), b l6.870(8), c 8.737(7) Ǻ,α 83.96(3), β 87.93(4), γ 65.24(2)�, Z=4 f.u .; R was 0.068 for N o 3181 'observed' (I > 3σ(I)) reflections. Mg-N are 2.12(2)-2.18(2) Ǻ, and Mg-Br are 2.452(7)-2.481(6) Ǻ. Calcium(II) bromide, by contrast, yields a disolvate , an infinite polymer, with the two MeCN ligands trans in a quasi-octahedral coordination sphere, and the polymer comprising a ... Ca(μ-Br)2Ca(μ-Br)2... linear array. Crystals of 1:2 CaBr2/MeCN (2) are orthorhombic, Pbam , a l4.252(3), b 8.539(2), c 4.2088(6) Ǻ, Z=2 f.u .; R 0.043 for N o 352. Ca-N is 2.46(1) Ǻ, and Ca-Br 2.8765(9) Ǻ. CaI2 and SrI2 yield pentasolvates as neutral, molecular species [( MeCN )5MX2] (3) and (4), with the halides trans in a pentagonal bipyramidal coordination sphere. They are isomorphous . orthorhombic, Pcab , a ≈ 18.4, b ≈ 14.6, c ≈ 14.3 Ǻ, Z = 8 f.u .; R were 0.042 and 0.059 for N o 2297 and 1489 respectively. Ca-I are 3.132(2), 3.116(2) Ǻ and Sr -I are 3.265(3), 3.238(3) Ǻ, while Ca-N are (range) 2.518(8)-2.566(8) Ǻ and Sr -N 2.68(2)-2.73(2) Ǻ.

Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. VII. Some Complexes of Group 2 Metal Halides With Aromatic N,N'-Bidentate Ligands

1996 ◽  
Vol 49 (1) ◽  
pp. 99 ◽  
Author(s):  
BW Skelton ◽  
AF Waters ◽  
AH White
Keyword(s):  
Room Temperature ◽  
The Novel ◽  
Bidentate Ligands ◽  
Nitrogen Base ◽  
One Dimensional ◽  
X Ray ◽  
L System ◽  
L Systems ◽  
Group 2 ◽  
Structural Characterizations

Syntheses and room-temperature single-crystal X-ray structural characterizations are recorded for a number of adducts of Group 2 halides with the aromatic N,N′- bidentate ligands L = 2,2'-bipyridine ( bpy ) and 1,10-phenanthroline ( phen ). One adduct of 1 : 1 MX2/L stoichiometry is recorded: [( bpy )Ca(μ-Br)(4/2)](∞ ׀ ∞) (1) is monoclinic, C 2/c, a l7.102(5), b 9.845(1), c 7.600(2) Ǻ, β 107.65(2)°, Z = 4 f.u .; conventional R on #1472; F ׀ at convergence was 0.057 for No 817 independent 'observed' ( I > 3σ(I)) reflections, the compound being a one-dimensional polymer… CaL (μ-Br)2CaL(μ-Br)2…, with six-coordinate calcium, cis-CaN2(μ-Br)4, on a twofold axis. 1 : 2 MX2/L systems have been described for two types of array: [( bpy )2CaI2] (2), orthorhombic, Pnca, a 16.914(4), b 13.80(1), c 9.290(4) Ǻ, Z = 4 f.u .; R 0.039 for No 1738, is discrete mononuclear, containing cis-CaN4I2 six-coordinate calcium, whereas the barium analogue is an infinite one-dimensional polymer, [( bpy )2Ba(μ-I)(4/2)](∞׀ ∞) (3), triclinic, Pī, a 11.318(2), b 11.078(2), c 9.206(4) Ǻ, α 80.87(2), β 77.52(2), γ 87.53(1)°, Z = 2 f.u .; R 0.032 for No 4154, with eight-coordinate (N2)2Ba(μ-I)4. The perchlorate analogue, [( bpy )2Ba(μ-OClO2O)(4/2)](∞ ׀ ∞) (4), although of similar stoichiometry, has a trans-rather than a cis-linked chain; it is monoclinic, P 21/c, a 6.606(2), b 18.661(7), c 19.440(8) Ǻ, β 109.45(4)°, Z = 4 f.u .; R 0.044 for No 4060, with μ-I replaced by O,O'-ClO4 bridging units and eight-coordinate barium, (N2)2BaO4. The 1 : 3 MX2/L system is represented (as its hemi( bipyridine ) 'solvate') by mononuclear [( bpy )3SrI2].0.5bpy (5), monoclinic, P 21/c, a 20.834(8), b 9.735(4), c 18.460(7) Ǻ, β 114.87(3)°, Z = 4 f.u .; R 0.039 for No 3711, containing eight-coordinate strontium, [(N2)3SrI2]; there is also an isomorphous calcium/ perchlorate analogue [( bpy )3Ca(OClO3)2].0.5bpy (6), a 21.413(6), b 9.813(4), c 18.659(2) Ǻ, β 115.67(2)°, R 0.057 for No 3090, in which unidentate O-ClO4 ligands replace the iodine about the metal atom. A 1 : 4 adduct is obtained with CaI2/phen; ionic [Ca( phen )4] I2 (7), triclinic, Pī , a 14.703(3), b 13.292(3), c 11.38(1) Ǻ, α 92.78(4), β 96.15(4), γ 105.22(2)°, Z = 2 f.u ., R 0.053 for No 3658, contains eight-coordinate Ca(N2)4 arrays, while the novel 1 : 5 adduct [ Ba ( phen )4] I2.MeCN (8) is triclinic, Pī , a 12.170(6), b 13.760(7), c 18 254(8) Ǻ, α 77.05(9), ,β 71.96(4), γ 70.83(9)°, Z = 2 f.u ., R 0.040 for No 4447, containing 10-coordinate barium, [ Ba (N2)5]. A 1 : 4 adduct formed with BaBr2 is [ BrBa( phen )4] Br.MeOH (9), triclinic, Pī , a 17.748(4), b 17.418(2), c 15.535(7) Ǻ, α 91.63(2), β 100.53(3), γ 115.39(1)°, Z = 4 f.u ., R 0.062 for No 4092, containing nine-coordinate barium, [ BrBa (N2)4].

The structures and phase transitions in 4-aminopyridinium tetraaquabis(sulfato)iron(III), (C5H7N2)[FeIII(H2O)4(SO4)2]

2019 ◽  
Vol 75 (6) ◽  
pp. 1144-1151
Author(s):  
Tamara J. Bednarchuk ◽  
Wolfgang Hornfeck ◽  
Vasyl Kinzhybalo ◽  
Zhengyang Zhou ◽  
Michal Dušek ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Single Crystal ◽  
Room Temperature ◽  
Variable Temperature ◽  
Temperature Phase ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Hybrid Compound ◽  
Space Group ◽  
X Ray

The organic–inorganic hybrid compound 4-aminopyridinium tetraaquabis(sulfato)iron(III), (C5H7N2)[FeIII(H2O)4(SO4)2] (4apFeS), was obtained by slow evaporation of the solvent at room temperature and characterized by single-crystal X-ray diffraction in the temperature range from 290 to 80 K. Differential scanning calorimetry revealed that the title compound undergoes a sequence of three reversible phase transitions, which has been verified by variable-temperature X-ray diffraction analysis during cooling–heating cycles over the temperature ranges 290–100–290 K. In the room-temperature phase (I), space group C2/c, oxygen atoms from the closest Fe-atom environment (octahedral) were disordered over two equivalent positions around a twofold axis. Two intermediate phases (II), (III) were solved and refined as incommensurately modulated structures, employing the superspace formalism applied to single-crystal X-ray diffraction data. Both structures can be described in the (3+1)-dimensional monoclinic X2/c(α,0,γ)0s superspace group (where X is ½, ½, 0, ½) with modulation wavevectors q = (0.2943, 0, 0.5640) and q = (0.3366, 0, 0.5544) for phases (II) and (III), respectively. The completely ordered low-temperature phase (IV) was refined with the twinning model in the triclinic P{\overline 1} space group, revealing the existence of two domains. The dynamics of the disordered anionic substructure in the 4apFeS crystal seems to play an essential role in the phase transition mechanisms. The discrete organic moieties were found to be fully ordered even at room temperature.

Notizen: Einkristall-Strukturdaten einiger Fluoride und Cyanide A2IBIMIIIX6 der Elpasolithfamilie / Single Crystal Structural Data of Some Fluorides and Cyanides A2IBIMIIIX6 of the Elpasolite Family

1975 ◽  
Vol 30 (5-6) ◽  
pp. 462-464 ◽  
Author(s):  
R. Haegele ◽  
W. Verscharen ◽  
D. Babel
Keyword(s):  
Single Crystal ◽  
Structural Data ◽  
Space Group ◽  
X Ray ◽  
Lattice Constants ◽  
Structure Determinations ◽  
Crystal Structural Data ◽  
Crystal Structural

The parameters of complete X-ray structure determinations are given for the fluoridesRb2NaFeF6 and Rb2KFeF6 (cubic), Cs2NaCrF6 and Cs2NaFeF6 (hexagonal-rhom-bohedral) and Cs2LiGaF6 (hexagonal). Space group and lattice constants of the monoclinic cyanides Cs2BFe(CN)6 (B = Na, K, Rb) are reported as well.

Structural Systematics of 2/4-Nitrophenoxide Complexes of Closed-Shell Metal Ions. VII Acid Salts of the 4-Nitrophenoxides of Group 2

1998 ◽  
Vol 51 (8) ◽  
pp. 785 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Room Temperature ◽  
Calcium Salt ◽  
Three Dimensional ◽  
Closed Shell ◽  
The Other ◽  
X Ray ◽  
C 23 ◽  
Structure Determinations ◽  
Group 2 ◽  
Acid Salts

Room-temperature single-crystal X-ray structure determinations are recorded for a number of Group 2 4-nitrophenoxide acid salts, variously hydrated M(4-np)2.x(4-npH).yH2O. Ca(4-np)2.2(4-npH).8H2O is monoclinic, P 21/n, a 30·52(1), b 10·027(1), c 23·65(2) Å, β 116·3(5)°, Z = 8, conventional R on |F| being 0·058 for No 5092 independent ‘observed’ (I > 3s(I)) reflections. Sr(4-np)2.2(4-npH).8H2O, based on a subcell of the former, is monoclinic, P 21/c, a 15·576(5), b10·081(6), c 24·20(2) Å, β 117·99(5)° , Z = 4, R 0·054 for No 2908. Ba(4-np)2.2(4-npH).4H2O is orthorhombic, Fdd2, a 28·01(1), b 19·90(1), c 10·692(7)Å, Z = 8, R 0·028 for No 1967. The strontium array (and that of the calcium salt developed from it) may be represented as [(H2O)6Sr(4-npH.4-np)] (4-npH.4-np), a neutral ligand being unsymmetrically chelated to the strontium through the nitro group, with a quasi-parallel counter ion hydrogen-bonded to it by phenoxide confrontation. The other two 4-np residues make up a similar phenoxide-confronting pair (4-npH.4-np), the hydrogen being more intimately associated with one moiety. The barium salt is also an interesting array: the 10-coordinate barium lies on a crystallographic 2 axis, in an environment of two pairs of symmetry-related nitro-chelating ligand anions, and a pair of nitro-O coordinating neutral 4-npH ligands; the whole [(H2O)4Ba(4-np)2(4-npH)2] array may be envisaged as a single neutral (super)molecule. Hydrogen bonds between confronting phenoxides of the neutral 4-npH components of the parent and the 4-np- components of neighbouring molecules link the whole into a three-dimensional array.

Structural Systematics of 2/4-Nitrophenoxide Complexes of Closed-Shell Metal Ions. V 2-Nitrophenoxides of Group 2

1998 ◽  
Vol 51 (8) ◽  
pp. 761 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Allan H. White
Keyword(s):  
Water Molecule ◽  
Metal Ions ◽  
Single Crystal ◽  
Room Temperature ◽  
Closed Shell ◽  
Magnesium Salt ◽  
Water Molecules ◽  
One Dimensional ◽  
X Ray ◽  
Group 2

Room-temperature single-crystal X-ray studies are recorded for 2-nitrophenoxide salts of Group 2 metals, variously hydrated M(2-np)2.xH2O, M = Mg, Ca, Sr; the structure of the barium analogue has been previously recorded. Mg(2-np)2.2H2O is monoclinic, P21/a, a 7·377(1), b 7·518(1), c 12·877(3) Å, β 106·58(2)°, Z = 2; conventional R on |F| 0·13 for No 508 independent ‘observed’ (I > 3σ(I)) reflections. Ca(2-np)2.H2O is monoclinic, C2, a 25·92(1), b 7·176(3), c 3·660(4) Å, β 93·66(5)°, Z = 2, R 0·061 for No 541. M(2-np)2.4H2O, M = Ca, Sr, are isomorphous, monoclinic, C2/c, a ≈ 31·3, b ≈ 8·1, c ≈ 12·8 Å, β 103°, Z = 8; R was 0·056, 0·055 forNo 1988, 1744 respectively. The magnesium salt is a discrete molecular array disposed about a crystallographic inversion centre with chelating phenoxide ligands: trans-[Mg(2-np)2(OH2)2]. The calcium monohydrate salt is a novel one-dimensional polymer with a ... Ca(µ-O)2Ca(µ-O)2Ca ... spine, the ligand pairs chelating the calcium with phenoxide-O additionally bridging. The seven-coordinate calcium atoms lie on the crystallographic 2 axis with the water molecule, also on that axis, making up a seven-coordinate environment. The tetrahydrate is also a one-dimensional polymer with a similar spine, the bridging oxygen atoms derivative of water molecules. A chelating ligand and two further water molecules make up an eight-coordinate metal environment, with the free anions interleaving stacks of coordinated anions up c.

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