Strontium tetra­fluoro­borate. Erratum

Erratum to Acta Cryst. (2007), C63, i75–i76

Unknown <i>cis</i>-[(DMSO)₂ClCu^II(μ-Cl)₂Cu^IICl(DMSO)₂] isomer obtained via new [Cu₄Cl₈(DMSO)₈(hmta)] template complex

<p>A missed <i>cis</i> isomeric form of a well-known <i>trans</i>-[CuCl₂(DMSO)₂]_n complex has been prepared via the tetranuclear [Cu₄Cl₈(DMSO)₈(<b>hmta</b>)] complex. Structurally, both complexes were found to be molecular i.e. [Cu₄Cl₈(DMSO)₈(<b>hmta</b>)] consists of isolated tetracoordinated hexamethylenetetramine molecules, whereas the <i>cis</i>-complex consists of isolated [(DMSO)₂ClCu^II(μ-Cl)₂Cu^IICl(DMSO)₂] clusters. It should also be noted that the <i>cis</i>-configuration of DMSO molecules in [(DMSO)₂ClCu^II(μ-Cl)₂Cu^IICl(DMSO)₂] was directly transferred from that of [Cu₄Cl₈(DMSO)₈(<b>hmta</b>)], while the <i>trans</i>-[CuCl₂(DMSO)₂]_n isomer was always formed as a final stable product.</p

Low-temperature modification of Ba(BF4)2(H2O)3

The crystal structure of the low-temperature modification of Ba(BF4)2(H2O)3, barium bis(tetrafluoridoborate) trihydrate, was determined at 150 K. In contrast to the room-temperature modification, which crystallizes in the space group C2221 [a = 7.1763 (6), b = 18.052 (2), c = 7.1631 (6) Å, V = 927.93 (15) Å3 at 300 K, Z = 4; Charkin et al. (2023). J. Struct. Chem. 64, 253–261], the low-temperature phase is monoclinic, space group P21 [a = 7.0550 (4), b = 7.1706 (3), c = 9.4182 (6) Å, β = 109.295 (7)o, V = 449.68 (5) Å3, Z = 2]. The structure of the low-temperature modification of Ba(BF4)2(H2O)3 features O—H...F and O—H...O hydrogen bonding between water molecules and BF4− anions. One of the coordinating water molecules in the low-temperature modification is disordered over two sets of sites

Copper(I) bromide and chloride complexes with urotropine and triethylenediamine: synthesis, crystal structure, and Raman characterization^*

<p>In the present study, the oxidative dissolution of metallic copper has been explored with the intention to prepare some new complexes with urotropine (<i>hmta</i>) and triethylenediamine (<i>dabco</i>) ligands. All the compounds synthesized were characterized by single-crystal X-ray diffraction and Raman spectroscopy<i>.</i> Reactions performed in a DMSO/CuCl₂∙2H₂O mixture resulted in [(μ-Cl)₂Cu^I(<i>hdabco</i>⁺)Cu^I(μ-Cl)(κ<i>S</i>-DMSO)]_n and [Cu^ICl(<i>hmta</i>)₂] complexes. Their isostructural bromide analogs [(μ-Br)₂Cu^I(<i>hdabco</i>⁺)Cu^I(μ-Br)(κ<i>S</i>-DMSO)]_n and [Cu^IBr(<i>hmta</i>)₂] were prepared by the reaction of elemental copper with respective ligands in a DMSO/CBr₄ mixture. Early interrupted reaction of the copper wire with the DMSO/CBr₄/<i>dabco</i> solution resulted in an appearance of crystals of the [Cu^I₂Br₂(CO)₂(<i>dabco</i>)]_n carbonyl complex on the copper surface. It arises with the participation of <i>in situ</i> formed carbon monoxide. Despite the identical stoichiometry, the crystal structure of the [Cu₂Br₂(CO)₂(<i>dabco</i>)]_n complex is markedly different from that of a known [Cu₂Cl₂(CO)₂(<i>dabco</i>)]_n analog.</p

Tetrahydrated bis(monoaqua-bis(ethylenediamine)copper(II))-diaqua-bis(ethylenediamine)copper(II) dicitrate

The crystals of the first copper(II) ethylenediamine complex containing citrate anion have been prepared and characterized. Despite the archetypical character of the copper(II) ethylenediamine complexes, some structural peculiarities were found to be interesting since they are quite rare even among the mentioned type of the complex compounds i.e. a presence of both mono and diaqua-bis(ethylenediamine)copper(II) cations together in the same crystal structure, intramolecular hydrogen bonding of the citric anion, cis,trans-configuration of the citric anion and the disordered C-C bond of the ethylenediamine molecule in the monoaquabis(ethylenediamine)copper(II) cation, which in fact is a co-existence of two energetically close dd and dk conformers. The Raman as well as FTIR spectra were recorded and discussed. Finally, the magnetic measurements have shown paramagnetic behavior of the prepared complex in a wide range of temperatures