β-Alaninium picrate: A new salt with di-β-alaninium dimeric cation

β-Alaninium picrate crystallizes in the form of yellow columns, in the triclinic system (space group P 1 ¯ , Z = 2). The asymmetric unit contains one β-alaninium cation and one picrate anion. Nevertheless, the unit cell comprises a dimeric centrosymmetric β-Ala+⋯β-Ala+ cation and two picrate anions. The O⋯O distance (2.636(2) Å) in the dimeric cation is among the shortest distances of known salts with A+⋯A+ type dimeric cations. The infrared and Raman spectra are shown and discussed. A comparison of known crystals with β-Ala+⋯β-Ala+ cations is presented, which shows that four different types can be distinguished.