Effect of counter-ion on packing and crystal density of 5,5'-(3,3'-bi[1,2,4-oxa-diazole]-5,5'-di-yl)bis-(1-tetra-zol-1-olate) with five different cations.

In energetic materials, the crystal density is an important parameter that affects the performance of the material. When making ionic energetic materials, the choice of counter-ion can have detrimental or beneficial effects on the packing, and therefore the density, of the resulting energetic crystal. Presented herein are a series of five ionic energetic crystals, all containing the dianion 5,5'-(3,3'-bi[1,2,4-oxa-diazole]-5,5'-di-yl)bis-(1-tetra-zol-1-olate), with the following cations: hydrazinium () (2NH·CNO), hydroxyl-ammonium () 2NHO·CNO [Pagoria (2017).

Two Cu complexes of 3,4,5-tri-methyl-1-pyrazole.

The crystal structure of complexes of 3,4,5-tri-methyl-1-pyrazole with CuCl·2HO and Cu(NO)·2.5HO are presented, namely di-μ-chlorido-bis[chloridobis(3,4,5-trimethyl-1-pyrazole-κ)copper(II)], [CuCl(CHN)] () and aquatetrakis(3,4,5-trimethyl-1-pyrazole-κ)copper(II) dinitrate, [Cu(CHN)(HO)](NO) (), and compared to the previously determined structures for 3-methyl-1-pyrazole and 3,5-di-methyl-1-pyrazole. CuCl forms a 2:1 ligand-to-metal chloride-bridged complex with 3,4,5-tri-methyl-1-pyrazole, with a square-pyramidal coordination geometry about each copper(II) center.

Supramolecular architectures with π-acidic 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine cavities: role of anion-π interactions in the remarkable stability of Fe(II) metallacycles in solution.

The comprehensive investigation reported herein provides compelling evidence that anion-π interactions are the main driving force in the formation of self-assembled Fe(II)-templated metallacycles with bptz [3,6-bis(2-pyridyl)-1,2,4,5-tetrazine] in high yields. It was demonstrated by X-ray crystallography, (1)H NMR, solution and solid-state MAS (19)F NMR spectroscopies, CV and MS studies that the anions [X](-) = [BF(4)](-), [ClO(4)](-) and the anions [Y](-) = [SbF(6)](-), [AsF(6)](-), [PF(6)](-) template molecular squares [Fe(4)(bptz)(4)(CH(3)CN)(8)][X](8) and pentagons [Fe(5)(bptz)(5)(CH(3)CN)(10)][Y](10), respectively. The X-ray structures of [{Fe(4)(bptz)(4)(CH(3)CN)(8)}⊂BF(4)][BF(4)](7) and [{Fe(5)(bptz)(5)(CH(3)CN)(10)}⊂2SbF(6)][SbF(6)](8) revealed that the [BF(4)](-) and [SbF(6)](-) anions occupy the π-acidic cavities, establishing close directional F···C(tetrazine) contacts with the tetrazine rings that are by ~0.

Anion-templated self-assembly of highly stable Fe(II) pentagonal metallacycles with short anion-π contacts.

The crystal structures of the self-assembled metallapentacycles [{Fe(5)(bptz)(5)(CH(3)CN)(10)} ⊂ 2SbF(6)][SbF(6)](8) (1) and [{Fe(5)(bmtz)(5)(CH(3)CN)(10)} ⊂ SbF(6)][SbF(6)](9) (2) with the π-acidic ligands bptz (3,6-bis(2-pyridyl)-1,2,4,5-tetrazine) and bmtz (3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine), respectively, revealed cationic pentagons templated by [SbF(6)](-) ions. The short anion-π contacts established between the anions and the tetrazine rings play an important role in the stability of the pentagons.

Solvent-enhanced magnetic ordering temperature for mixed-valent chromium hexacyanovanadate(II), Cr(II)0.5Cr(III)[V(II)(CN)6].zMeCN, magnetic materials.

The reaction of V(III)(THF)3Cl3 with NEt(4)CN in acetonitrile (MeCN) forms (NEt4)3[V(III)(CN)6].4MeCN (1), which after characterization was used as a molecular building block toward the synthesis of Prussian blue structured magnets. The reaction of 1 with [Cr(II)(NCMe)4](BF4)2 forms Cr(II)(0.