This collection highlights the diversity and quality of research conducted by Latin American scientists, and emphasizes the interdisciplinary nature of crystallography, highlighting its connections with other research fields and presenting innovative and thought-provoking studies.

Fast readout event-based electron counting (EBEC) is a promising detection strategy to determine accurate ab initio structures of beam-sensitive small molecules by MicroED. A fast EBEC approach enhances the dynamic range of MicroED data by limiting the likelihood of coincidence loss (CL) – the undercounting of electrons due to their spatially and temporally unresolved arrival on a direct electron detector. As implemented by new counting detectors, fast EBEC allows structure-worthy data sets to be captured from individual small-molecule crystals in under a minute.

Analysis of the crystal structure of [dihydrobis(pyrazol-1-yl)borato]tris(tetrahydrofuran)magnesium(II) tetrabenzylborate reveals a pronounced boat-shaped central Mg(N–N)₂B moiety with a weak pseudo-axial B—H…Mg interaction. A novel counter-ion, [B(C₇H₇)₄)]⁻, has been obtained by the reaction between KBH₄ and (PhCH₂)MgCl to produce a polymeric potassium tetrabenzylborate with predominant (η⁶-C₆H₅)…K and (η³-C₆H₅)…K interactions.

Two novel benzylamine-based crown ether inclusion complexes have been synthesized and they exhibit nonlinear optical properties. Notably, [(C₆H₅–CH₂–NH₃)(18-crown-6)][TfNMs] [TfNMs = methylsulfonyl)(trifluoromethylsulfonyl)azanide] represents the first example of an 18-crown-6 complex with TfNMs as the counter-ion, enriching the family of crown ether inclusion complexes.

The crystal structure and thermal expansion of Rb₂Ca₂Si₂O₇ have been investigated from single-crystal diffraction data. The structural relationships with other pyrosilicates are discussed.

A new crystal structure of the fluorine analogue of busulfan was obtained and analyzed using single-crystal X-ray diffraction and various computational methods. The crystal structure is stabilized by, among other factors, hydrogen bonds, as confirmed by density functional theory calculations.

The cationic tris-complex [Ni^II(d-tG)₃]²⁺ features bidentate N,S-chelating ligands in a distorted fac-S₃N₃ octahedral geometry with one Δ and two Λ isomers observed in the three independent cations, each with crystallographic threefold rotation symmetry.

The synthesis and characterization of six novel coumarin derivatives containing O and S atoms are described. Hirshfeld surface and energy framework analyses show that stacked π–π ring interactions occur for all the structures and various hydrogen-bond interactions link the stacks to form three-dimensional energy frameworks.