search results
results of search on CRYSTALLOGRAPHY JOURNALS ONLINE
6 citations found for Nunes, S.
Search for Nunes, S. in the World Directory of Crystallographers
Results 1 to 6, sorted by name:
![s logo](https://journals.iucr.org/logos/jicons/s_36x36.png)
X-ray powder diffraction at the upgraded and comissioned XRD1 beamline is reported. The beamline operates in the 5.5–14 keV range with a photon flux of 3.4 × 1010 photons s−1 at 8 keV.
![e logo](https://journals.iucr.org/logos/jicons/e_36x36.png)
Open
access
![Open Access](/logos/buttonlogos/open.png)
The molecule of the title compound C7H8N4O·0.5H2O, alternatively called (E)-1-(pyridin-4-ylmethylene)semicarbazide hemihydrate, is in the E conformation and is almost planar; the r.m.s. deviation of the positions of the atoms of the pyridine ring from the best-fit plane is 0.0039 Å. The C, N and O atoms of the rest of the molecule sits close on this plane with a largest deviation of 0.115 (4) Å for the O atom of the semicarbazone moiety. There is an intramolecular N—H
N hydrogen bond. In the crystal, molecules are linked into an infinite three-dimensional network by classical N—H
Os (s = semicarbazone) and Ow—H
N (w = water) hydrogen bonds.
![...](/logos/entities/ctdot_rmgif.gif)
![...](/logos/entities/ctdot_rmgif.gif)
![...](/logos/entities/ctdot_rmgif.gif)
![e logo](https://journals.iucr.org/logos/jicons/e_36x36.png)
The title complex, [VCl2(dtbeda)(thf)2] (dtbeda is N,N'-di-tert-butylethane-1,2-diamine), was prepared from the reaction of [V2Cl3(thf)6]2[Zn2Cl6] with dtbeda in refluxing thf. The crystal structure of [VCl2(dtbeda)(thf)2] exhibits chlorides in trans positions in a distorted octahedral geometry around the vanadium site. The asymmetric unit consists of one-half of the complex, which is located on a twofold rotation axis in space group C2/c.
![a logo](https://journals.iucr.org/logos/jicons/a_36x36.png)
![a logo](https://journals.iucr.org/logos/jicons/a_36x36.png)
![e logo](https://journals.iucr.org/logos/jicons/e_36x36.png)
The title complex, (C6H18N2)[V2Cl5(C6H16N2)2](C24H20B).C4H8O, was prepared by the reaction of [V2Cl3(THF)6](BPh4) with [FeCl2(tmeda)2] in the presence of one equivalent of tmeda (tmeda = N,N,N′,N′-tetramethylethylenediamine) in methanol. The crystal structure shows the tmeda to be coordinated to the vanadium core groups. The exchange of the diamine from iron to vanadium sheds new light on the mechanism of self-assembly of triangulo trinuclear complexes.