Nalazite se na CroRIS probnoj okolini. Ovdje evidentirani podaci neće biti pohranjeni u Informacijskom sustavu znanosti RH. Ako je ovo greška, CroRIS produkcijskoj okolini moguće je pristupi putem poveznice www.croris.hr
izvor podataka: crosbi

Dimerisation and oxygen loss upon crystallisation of nitroso compounds (CROSBI ID 482830)

Prilog sa skupa u zborniku | sažetak izlaganja sa skupa

Višnjevac, Aleksandar ; Milovac, Srđan ; Šimunić- Mežnarić, Vesna ; Kojić-Prodić, Biserka ; Vančik, Hrvoj Dimerisation and oxygen loss upon crystallisation of nitroso compounds // 11th Slovenian-Croatian crystallographic meeting - book of abstracts / Leban, Ivan ; Popović, Stanko (ur.). Ljubljana: Univerza v Ljubljani, 2002. str. 28-28

Podaci o odgovornosti

Višnjevac, Aleksandar ; Milovac, Srđan ; Šimunić- Mežnarić, Vesna ; Kojić-Prodić, Biserka ; Vančik, Hrvoj

engleski

Dimerisation and oxygen loss upon crystallisation of nitroso compounds

Most of the organic nitroso compounds exist as colourless dimers in solid state, and/or as green or blue monomers in solution.1 Crystallisation process implies simultaneous dimerisation. Nevertheless, these compounds reveal reversible dissociation/association under photochemical conditions in solid state, and as such they represent a simple and effective photochromic system.2 Dimers of p-bromonitrosobenzene (1), p- iodonitrosobenzene (2), p-nitronitrosobenzene (3) and p-methylnitrosobenzene (4) were studied by X- ray crystallography. Unprecedented lack of oxygen atoms in what was expected to be an azodioxy moiety was encountered in all of the presented structures. Furthermore, the structures 3 and 4 (Figs. 1 and 2) reveal disorder of the azo group over two positions, with s.o. 0.70 and 0.30. Two independent positions of nitrogen atoms appeared clearly in a Fourier difference map, whereas it was impossible to resolve discrete positions of disordered C-atoms of the benzene rings which, as a consequence, reveal slightly increased values of displacement parameters. For structure 3, the non- centrosymmetric space group P21 is reported due to a large number of reflections disobeying extinction rules for P21/c (in which, however, refinement converges as well). Molecules of 1 and 2 reveal crystallographic inversion centre at the midpoint of the N-N bond, having half a molecule in an asymmetric unit of the space groups P21/c and Pbcn, respectively. The molecule of 4 is of C1 symmetry, occupying general position.

dimerisation ; oxygen loss ; crystallisation ; nitroso compounds

nije evidentirano

nije evidentirano

nije evidentirano

nije evidentirano

nije evidentirano

nije evidentirano

Podaci o prilogu

28-28.

2002.

nije evidentirano

objavljeno

Podaci o matičnoj publikaciji

11th Slovenian-Croatian crystallographic meeting - book of abstracts

Leban, Ivan ; Popović, Stanko

Ljubljana: Univerza v Ljubljani

Podaci o skupu

11th Slovenian-Croatian Crystallographic Meeting

predavanje

27.07.2002-30.07.2002

Bohinj, Slovenija

Povezanost rada

Kemija