Intramolecular pi-pi stacking in diaquabis(2-hydroxybenzoato-kappaO)bis(1,10-phenanthroline-kappa2N,N')strontium(II).

In the title compound, [Sr(C7H5O3)2(C12H8N2)2(H2O)2], the Sr(II) ion is located on a twofold rotation axis and assumes a distorted square-antiprism SrN4O4 coordination geometry, formed by two phenanthroline (phen) ligands, two 2-hydroxybenzoate anions and two water molecules. Within the mononuclear complex molecule, intramolecular pi-pi stacking is observed between nearly parallel coordinated phen ligands, while normal intermolecular pi-pi stacking occurs between parallel phen ligands of adjacent complex molecules. Classic O-H...O and weak C-H...O hydrogen bonding helps to stabilize the crystal structure.