CeRu₂Al₁₀ with the YbFe₂Al₁₀ structure type

The structure of cerium diruthenium decaaluminium, CeRu₂Al₁₀, is characterized by seven crystallographic sites in space group Cmcm, viz. Ce in 4c, Ru in 8a, two Al atoms in 8g, two Al atoms in 8f and one Al atom in 8e. The structure can be interpreted as a stacking of alternating columns running along [001], each formed by only one type of Ru cuboid with composition RuAl₆ or CeRuAl₄.

2-Methyl-7-oxo-5,6,7,8-tetra­hydro­pyrimido­[4,5-d]­pyrimidin-3-ium chloride, a product of the thermal decomposition of nimustine hydro­chloride (ACNU)

The title compound, C₇H₉N₄O⁺·Cl⁻, was obtained as a product of the thermal decomposition of nimustine hydro­chloride (ACNU). In the crystal structure, intermolecular N—H...O hydrogen bonds link the cations into centrosymmetric dimers, which are further connected by N—H...Cl and C—H...Cl hydrogen bonding to form two-dimensional networks.