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51.
C. Momany K. Clinger M. L. Hackert N. S. Poonia 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(1):61-67
The complex Rb(B15C5)2NO3·H2O is monoclinic,P21/c,a=12.695(3),b=19.471(3),c=12.991(2)Å, =99.60(2)o,V=3166 Å3,D
c
=1.473 g/cm3 (163 K),D
c
=1.434 g/cm3 (298 K),D
o
=1.44 g/cm3 (298 K),T=163K,Z=4, MoK=0.71069 Å, 2(4o–53o), =16.43 cm–1,F(000)=1424. FinalR for the 4588 observed reflections (F>3) is 0.062. All ten oxygens of the two benzo-crowns are shown to coordinate to the rubidium ion (Rb...O,2.92 to 3.07 Å) forming a charge-separated sandwich. The nearest nitrate oxygen is displaced 6.51 Å from the rubidium ion and is hydrogen bonded to a water molecule.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82028 (28 pages) 相似文献
52.
W. S. Sheldrick N. S. Poonia 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(1):93-98
The 1:2 charge separated KNO3 complex with benzo-15-crown-5 (B15C5) has been crystallized from a 50% water-methanol solution. K(B15C5)2NO3·H2O is monoclinic,P21/c,a=12.717(2),b=19.569(2),c=13.025(3) Å, =100.79(1)o,Z=4,D
c
=1.37 g·cm–3. The X-ray structure was refined toR=0.052 for 3049 independent reflections withF
0
2
2.0(F
0
2
), collected with MoK radiation for a 2 -range of 4–44°. The K+ ion is coordinated tenfold in a crown sandwich through all five oxygen atoms of the macrocyclic ligand. Nitrate and water oxygens are not involved in the cation coordination sphere.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82031 (6 pages). 相似文献
53.
N. S. Poonia 《Mikrochimica acta》1969,57(1):217-220
Summary
m-(Mercaptoacetamido)phenol (m-MAP) is used as a reductant for the distinction and separation of SeO3
2–, SeO4
2–, TeO3
2–, and TeO4
2–.
Zusammenfassung m-(Merkaptoacetamido)-phenol wurde als Reduktionsmittel zur Unterscheidung und Trennung von SeO3 2–, SeO4 2–, TeO3 2– und TeO4 2– verwendet.相似文献
54.
K. Poonia S. Malik S. Maanju R. V. Singh 《Russian Journal of Coordination Chemistry》2008,34(5):339-343
The synthetic routes and spectroscopic studies of organotitanium(IV) and organozirconium(IV) complexes derived from azomethines,
1-acetylferrocenethiosemicarbazone (L1H) and 1-acetylferrocenesemi-carbazone (L2H), have been carried out in 1 : 1 and 1 : 2 stoichiometric ratios. Azomethines and their complexes have been characterized
by elemental analyses, conductance measurements, molecular weight determinations, and spectral studies. The electronic, IR,
and 1H NMR and 13C NMR spectral data indicate that azomethines act as bidentate ligands and coordinate to the metal (Ti or Zr) via nitrogen
and the sulfur or oxygen atoms giving trigonal bipyramidal and octahedral geometries for the resulting complexes. All the
ligands and their complexes have been screened for their biological activity on several pathogenic fungi and bacteria and
were found positive in this respect.
The text was submitted by the authors in English. 相似文献
55.
56.
Twelve complexes 1-12 of general category [M(ligand)(anion)(x)(water)(y)], where ligand = N,N,N',N'-tetrakis(2-hydroxypropyl/ethyl)ethylenediamine (HPEN/HEEN), anion = anions of picric acid (PIC), 3,5-dinitrobenzoic acid (DNB), 2,4-dinitrophenol (DNP), and o-nitrobenzoic acid (ONB), M = Ca(2+), Sr(2+), Ba(2+), or Na(+), x = 1 and 2, and y = 0-4, were synthesized. All of these complexes were characterized by elemental analysis, IR, (1)H and (13)C NMR, and thermal studies. X-ray crystal studies of these complexes 1-12, [Ca(HPEN)(H(2)O)(2)](PIC)(2).H(2)O (1), [Ca(HEEN)(PIC)](PIC) (2), Ba(HPEN)(PIC)(2) (3), [Na(HPEN)(PIC)](2) (4), Ca(HPEN)(H(2)O)(2)](DNB)(2).H(2)O (5),Ca(HEEN)(H(2)O)](DNB)(2).H(2)O (6), [Sr(HPEN)(H(2)O)(3)](DNB)(2) (7), [Ba(HPEN)(H(2)O)(2)](DNB)(2).H(2)O](2) (8), [[Ba(HEEN)(H(2)O)(2)](ONB)(2)](2) (9), [[Sr(HPEN)(H(2)O)(2)](DNP)(2)](2) (10), [[Ba(HPEN)(H(2)O)(2)](DNP)(2)](2) (11), and [Ca(HEEN)(DNP)](DNP) (H(2)O) (12), have been carried out at room temperature. Factors which influence the stability and the type of complex formed have been recognized as H-bonding interactions, presence/absence of solvent, nature of the anion, and nature of the cation. Both the ligands coordinate the metal ion through all the six available donor atoms. The complexes 1 and 5-11 have water molecules in the coordination sphere, and their crystal structures show that water is playing a dual character. It coordinates to the metal ion on one hand and strongly hydrogen bonds to the anion on the other. These strong hydrogen bonds stabilize the anion and decrease the cation-anion interactions by many times to an extent that the anions are completely excluded out of the coordination sphere and produce totally charge-separated complexes. In the absence of water molecules as in 2 and 3 the number of hydrogen bonds is reduced considerably. In both the complexes the anions case interact more strongly with the metal ion to give rise to a partially charge-separated 2 or tightly ion-paired 3 complex. High charge density Ca(2+) forms only monomeric complexes. It has more affinity toward stronger nucleophiles such as DNP and PIC with which it gives partially charge-separated eight-coordinated complexes. But with relatively weaker nucleophile like DNB, water replaces the anion and produces a seven coordinated totally charge-separated complex. Sr(2+) with lesser charge/radius ratio forms only charge-separated monomeric as well as dimeric complexes. Higher coordination number of Sr(2+) is achieved with coordinated water molecules which may be bridging or nonbridging in nature. All charge-separated complexes of the largest Ba(2+) are dimeric with bridging water molecules. Only one monomeric ion-paired complex was obtained with Ba(PIC)(2). Na(+) forms a unique dinuclear cryptand-like complex with HPEN behaving as a heptadentate chelating-cum-bridging ligand. 相似文献
57.
M. S. Hundal Geeta Sood Parveen Kapoor N. S. Poonia 《Journal of chemical crystallography》1991,21(2):201-204
The title compound C16H10N5O7Li is triclinic, witha=14.51(1),b=6.90(2),c=9.10(1) Å,=101.5(1),=67.1(2), =105.6°(1),Z=2 and space groupP¯1. Data were measured by photographic methods. The structure was solved by direct methods, and refined by full matrix least-squares. The refinement, based on 1337 reflections, gave the rather highR value of 0.11 because of poor quality data. The complex is dimeric. The coordination around the cation is distorted square-pyramidal. Two coordination sites are occupied by the nitrogen atoms of the bipyridyl ligand, two by the phenolic oxygen and oxygen ofo-nitro group, and the fifth coordination site is occupied by the phenolic oxygen belonging to the symmetry-related molecule (1–x,–y,1–z). Both oxygens act as bridges to form the dimer. The bridging is unsymmetrical, with Li-O (phenolic)=1.84(2) Å and Li1-O (phenolic)=2.16(2) Å (whereI=1–x,–y, 1–Z). 相似文献
58.
59.
60.