Search results for "SSBA"
showing 10 items of 454 documents
C-switches: Increasing switch radix with current integration scale
2011
In large switch-based interconnection networks, increasing the switch radix results in a decrease in the total number of network components, and consequently the overall cost of the network can be significantly reduced. Moreover, high-radix switches are an attractive option to improve the network performance in terms of latency, since hop count is also reduced. However, there are some problems related to the integration scale to design such single-chip switches. In this paper we discuss key issues and evaluate an interesting alternative for building high-radix switches going beyond the integration scale bounds. The idea basically consists in combining several current smaller single-chip swi…
A trigonal prismatic anionic iron(iii) complex of a radical o-iminobenzosemiquinonate derivative: structural and spectral analyses
2017
A new iron(III) complex, [Et3NH][FeIII(L2−˙)2] (1) with a substituted o-aminophenol based ligand is reported. Complex 1 is an anionic complex with a triethylammonium cation in the lattice. It contains two O,O,N-coordinated o-iminobenzosemiquinonate(2−) radical anions with an Fe(III) centre in a high-spin configuration. The crystal structure of 1 was determined by X-ray diffraction, which revealed a trigonal prismatic coordination environment whose electronic structure was established by various physical methods including EPR, Mossbauer spectroscopy and variable-temperature (2–300 K) magnetic susceptibility measurements. Electrochemical analysis indicated primarily ligand-centred redox proce…
Bis-macrocyclic Ligands with Two Ferrocenyl End Groups, and Their Tetranuclear Dicopper(I) Compounds
1999
A series of bismacrocyclic ligands with two ferrocenyl groups, exo/endo-1,1‘:1‘ ‘,1‘ ‘‘-[1,2,4,5-tetrakis(5-aza-2-thiahexa-5-enyl)benzene]bisferrocene (exo/endo-FeBeFe), 1,1‘:1‘ ‘,1‘ ‘‘-[1,2:1‘,2‘-tetrakis(5-aza-2-thiahexa-5-enyl)ethene]bisferrocene (1,2-FeEnFe), 1,1‘:1‘ ‘,1‘ ‘‘-[1,1‘:2,2‘-tetrakis(5-aza-2-thiahexa-5-enyl)ethene]bisferrocene (1,1-FeEnFe), 1,1‘:1‘ ‘,1‘ ‘‘-[tetrakis(5-aza-2-thiahexa-5-enyl)methane]bisferrocene (FeMeFe), and their dicopper(I) compounds have been synthesized and characterized (electrochemistry, IR, NMR and Mossbauer spectroscopy). The molecular structure of endo-FeBeFe has been determined by X-ray structure analysis and the copper(I)-induced discrimination of t…
Preparation and structural characterization of organotin(IV) complexes with ligands containing a hetero {N} atom and a hydroxy group or hydroxy and c…
2005
AbstractTwenty-two n-butyltin(IV) and t-butyltin(IV) complexes of ligands containing an –OH (–C@O) group or –OH and –COOHgroups and an aromatic {N} donor atom were prepared by metathetical reactions. On the basis of the FT-IR and Mo¨ssbauer spec-troscopic data, molecular structures were assigned to these compounds. The binding sites of the ligands were identified by means ofFT-IR spectroscopic measurements, and it was found that in most cases the organotin(IV) moiety reacts with the phenolic form ofthese ligands. In the complexes with –OH and –COOH functions, the –COOH group is coordinated to the organotin(IV) centres in amonodentate manner. The 119 Sn Mo¨ssbauer and the FT-IR studies suppor…
Mossbauer spectroscopic study of the thermal spin crossover in [Fe(II)(isoxazole)(6)](ClO(4))(2)
2008
The (57)Fe Mossbauer spectroscopy of mononuclear [Fe(II)(isoxazole)(6)](ClO(4))(2) has been studied to reveal the thermal spin crossover of Fe(II) between low-spin (S = 0) and high-spin (S = 2) states.Temperature-dependent spin transition curves have been constructed with the least-square fitted data obtained from the Mossbauer spectra measured at various temperatures between 84 and 270 K during a cooling and heating cycle. This compound exhibits an unusual temperature-dependent spin transition behaviour with T(C)(down arrow) = 223 and T(C)(up arrow) = 213 K occurring in the reverse order in comparison to those observed in SQUID observation and many other spin transition compounds. The comp…
Preparative and spectroscopic features of ferricenium tetrachloroferrate(III). Interconversion to diferricenium ?-oxo-bis[trichloroferrate(III)]
1985
Ferricenium tetrachloroferrate(III)(1), one of the more frequently cited ferricenium salts, has recently attracted biomedical interest because of its pronounced antineoplastic activity against Ehrlich ascites murine tumor. In this paper, synthetic methods are reinvestigated in an effort to prepare pure(1) free from a common contaminant, diferriceniumμ-oxo-bis(trichloroferrate)(3). The oxodiferrate, or mixtures of this salt with(1), can readily be converted into pure(1) under acidic conditions. Conversely, dimerization of(1) with participation of water to give the oxodiferrate(3) is brought about by recrystallization of the former from moist acetonitrile/methanol in the presence of base; thi…
Coordination properties of adenosine-5'-monophosphate and related ligands towards Me2Sn(IV)2+ in aqueous solution.
2002
Abstract The coordination of Me 2 Sn(IV) 2+ to adenosine-5′-monophosphate (AMP) and the related compounds d -ribose-5-phosphate (R5P), d -glucose-1-phosphate (G1P) and d -glucose-6-phosphate (G6P) in aqueous solution was investigated by means of potentiometric titration, and 1 H-, 31 P-NMR and Mossbauer spectroscopic methods in the pH range 2–11 ( I =0.1 M NaClO 4 , 298 K). The complex of AMP and Me 2 Sn(IV) 2+ precipitated at low pH was characterised by elemental analysis, FT-IR and Mossbauer spectroscopic methods. From a comparison of the p K values obtained in the presence and absence of metal ion and the stability constants for the different systems, the coordination of {N} is excluded,…
Synthesis, characterization of diorganotin(IV) complexes of N-(2-hydroxyarylidene)aminoacetic acid and antitumour screening in vivo in ehrlich ascite…
2001
Some new diorganotin(IV) complexes have been prepared by reacting potassium N-(2-hydroxyarylidene)aminoacetate with R2SnCl2(R = Me,nBu,Ph). The complexes have been characterized by 1H,13C,119Sn NMR, IR and 119mSn Mössbauer spectroscopic techniques in combination with elemental analysis. In the solid state, the complexes possess penta- and hexa-coordinated tin centres. The hexa-coordinated tin complexes were found to dissociate in solution, giving rise to penta-coordinated species as revealed by 119Sn NMR spectroscopy. Antitumour screening in vivo of the complexes L4snPh2,L4SnPh2· Ph3SnCl and L4SntBU2·t Bu2SnCl2 (L4 = N-(2-hydroxyacetophenone)aminoacetate) is also reported. Copyright © 2001 …
Pressure-induced magnetic switching and linkage isomerism in K0.4Fe4[Cr(CN)6]2.8 x 16 H2O: X-ray absorption and magnetic circular dichroism studies.
2008
The effect of applied pressure on the magnetic properties of the Prussian blue analogue K0.4Fe4[Cr(CN)6]2.8 x 16 H2O (1) has been analyzed by dc and ac magnetic susceptibility measurements. Under ambient conditions, 1 orders ferromagnetically at a critical temperature (T(C)) of 18.5 K. Under application of pressure in the 0-1200 MPa range, the magnetization of the material decreases and its critical temperature shifts to lower temperatures, reaching T(C) = 7.5 K at 1200 MPa. Pressure-dependent Raman and Mossbauer spectroscopy measurements show that this striking behavior is due to the isomerization of some Cr(III)-C[triple bond]N-Fe(II) linkages to the Cr(III)-N[triple bond]C-Fe(II) form. A…
Synthesis, antimony-121 mössbauer and infrared spectral characterization of antimony trifluoride and catecholatoantimony(III) fluoride adducts with t…
1988
Abstract The synthesis of the adducts SbF 3 (L) and (C 6 H 4 O 2 )SbF(L) [L = pyridine-2-carboxaldehyde- 2-pyridylhydrazone (paphyH); 2,2′:6′,2″-terpyridine (terpy) and 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tpta)] is reported. Infrared data are consistent with the occurred chelation from the terdentate ligand providing an overall pseudo-seven coordination at Sb. The stereoactivity of the antimony lone pair is inferred from the large value of the Mossbauer quadrupole coupling constant observed for all the compounds.