30 research outputs found
Exploration of Cd(II)/pseudohalide/di-2-pyridyl ketone chemistry - rational synthesis, structural analysis and photoluminescence
A systematic investigation of CdIJII)–(py)2CO–X systems (X = N3 −, NCO− and NCS−) was conducted, and the
following cadmium(II) coordination compounds [Cd(SCN)2{(py)2C(OCH3)(OH)}]n (1), [Cd2(SCN)4{(py)2-
C(OCH3)(OH)}2] (2), [Cd4(SCN)4{(py)2C(OCH3)(O)}4] (3), [Cd4(N3)4{(py)2C(OCH3)(O)}4] (4), [Cd4(N3)4{(py)2-
C(OH)(O)}2{(py)2C(OCH3)(O)}2] (5), [Cd4(NCO)4{(py)2C(OCH3)(O)}4] (6), [Cd4(NCO)4{(py)2C(OH)(O)}2{(py)2-
C(OCH3)(O)}2] (7), [Cd4(N3)2(NO3)2{(py)2C(OH)(O)}2{(py)2C(OCH3)(O)}2] (8) and
[Cd4(NCO)2(NO3)2{(py)2C(OH)(O)}2{(py)2C(OCH3)(O)}2] (9a and 9b) were successfully synthesized and characterized by single-crystal diffraction, X-ray powder diffraction (XRPD), differential scanning calorimetry
(DSC) analysis and IR spectroscopy. The fluorescence properties of 1–9 were studied in the solid state and
compared to the fluorescence of di-2-pyridyl ketone. The photoluminescence behaviour of 2–9 was also
investigated in acetonitrile solution. The X-ray studies demonstrated a cooperative impact of the organic ligand
and auxiliary inorganic ion on the final molecular architectures of the cadmium(II) coordination compounds.
Also, the essential roles of intermolecular interactions (hydrogen bonds, π–π stacking interactions
and weak O⋯S contacts) in the creation of molecular architectures were discussed
Synthesis, spectroscopic characterization, X-ray structure, and DFT calculations of [Cu(tppz)(SCN)(2)]
This article presents a combined experimental
and computational study of [Cu(tppz)(SCN)2], where ttpz
stands for 2,3,5,6-tetra-(2-pyridyl)pyrazine. The compound
has been studied by IR, UV–Vis spectroscopy, and single
crystal X-ray analysis. The geometry around copper atom
may be described as a distorted square pyramid. The
equatorial plane is defined by three nitrogen atoms of tppz
and one nitrogen atom of thiocyanate group. The apical site
is occupied by nitrogen atom of the second SCN- ion. The
electronic spectrum of [Cu(tppz)(SCN)2] was analyzed, and
bands were assigned through the DFT/TDDFT procedures
Molecular, spectroscopic, and magnetic properties of cobalt(II) complexes with heteroaromatic N(O)-donor ligands
New [Co(SCN)2(L)4/2] complexes, where
L = b-pic (1), pyCH2OH (2), py(CH2)3OH (3), 1,2,4-
triazolo[1,5-a]pyrimidine (4), [CoCl2(urotrop)2] (5), and
[Co(DMIM)3]Cl2 H2O (6) where urotrop = hexamethylenetetramine
and DMIM = 2,20-bis(4,5-dimethylimidazolyl)
were synthesized in simple reactions of CoCl2 6H2O
with ammonia thiocyanate and pyridine type ligands or
urotropine and diimidazolyl ligands with cobalt(II) chloride
in methanol solutions. The orthorhombic crystallization
for (1), (2), and (4), the monoclinic one for (3) and (5)
as well as the hexagonal one for (6) were found. The plots
of the overlap population density-of-states indicated nonbonding
character of the interactions between pyridine
derivatives ligands and cobalt(II) ions in the complexes
(1)–(4). The electronic spectra showed almost perfect
octahedral complex in the case of (6). The magnetic susceptibility
measurements revealed paramagnetic behavior
with low values of the Curie–Weiss temperature, positive
for complex (5) and negative for the other ones, although
the transition to collective magnetic state at low temperatures
for (4) and (5) was evidenced by an observation of
antiferromagnetic coupling with Ne´el temperature of 4.5 K
and the ferromagnetic one with Curie temperature of 10 K,
respectively
Structural approximations to positive maps and entanglement breaking channels
Structural approximations to positive, but not completely positive maps are
approximate physical realizations of these non-physical maps. They find
applications in the design of direct entanglement detection methods. We show
that many of these approximations, in the relevant case of optimal positive
maps, define an entanglement breaking channel and, consequently, can be
implemented via a measurement and state-preparation protocol. We also show how
our findings can be useful for the design of better and simpler direct
entanglement detection methods.Comment: 18 pages, 3 figure
Molecular, spectroscopic, and magnetic properties of cobalt(II) complexes with heteroaromatic N(O)-donor ligands
New [Co(SCN)2(L)4/2] complexes, where
L = b-pic (1), pyCH2OH (2), py(CH2)3OH (3), 1,2,4-
triazolo[1,5-a]pyrimidine (4), [CoCl2(urotrop)2] (5), and
[Co(DMIM)3]Cl2 H2O (6) where urotrop = hexamethylenetetramine
and DMIM = 2,20-bis(4,5-dimethylimidazolyl)
were synthesized in simple reactions of CoCl2 6H2O
with ammonia thiocyanate and pyridine type ligands or
urotropine and diimidazolyl ligands with cobalt(II) chloride
in methanol solutions. The orthorhombic crystallization
for (1), (2), and (4), the monoclinic one for (3) and (5)
as well as the hexagonal one for (6) were found. The plots
of the overlap population density-of-states indicated nonbonding
character of the interactions between pyridine
derivatives ligands and cobalt(II) ions in the complexes
(1)–(4). The electronic spectra showed almost perfect
octahedral complex in the case of (6). The magnetic susceptibility
measurements revealed paramagnetic behavior
with low values of the Curie–Weiss temperature, positive
for complex (5) and negative for the other ones, although
the transition to collective magnetic state at low temperatures
for (4) and (5) was evidenced by an observation of
antiferromagnetic coupling with Ne´el temperature of 4.5 K
and the ferromagnetic one with Curie temperature of 10 K,
respectively
Synthesis, thermal study and some properties of Gd(III), Tb(III), Dy(III) and Er(III) complexes with 4,4′-bipyridine and dibromoacetates
Synthesis, characterization, and molecular structure of Ru(II) complex containing 2,5-pyridinedicarboxylic acid
Characterization and cytotoxic effect of aqua-(2,2′,2′′-nitrilotriacetato)-oxo-vanadium salts on human osteosarcoma cells
Interaction for Immersive Analytics
International audienceIn this chapter, we briefly review the development of natural user interfaces and discuss their role in providing human-computer interaction that is immersive in various ways. Then we examine some opportunities for how these technologies might be used to better support data analysis tasks. Specifically, we review and suggest some interaction design guidelines for immersive analytics. We also review some hardware setups for data visualization that are already archetypal. Finally, we look at some emerging system designs that suggest future directions