https://journals.iucr.org/e/issues/2021/05/00/cq2043/cq2043.pdf

The crystal structure of dilithium potassium citrate monohydrate, Li+·2K+·C6H5O73−·H2O or LiK2C6H5O7·H2O, has been solved by direct methods and refined against laboratory X-ray powder diffraction data, and optimized using density functional techniques. The complete citrate trianion is generated by a crystallographic mirror plane, with two C and three O atoms lying on the reflecting plane, and chelates to three different K cations. The KO8 and LiO4 coordination polyhedra share edges and corners to form layers lying parallel to the ac plane. An intra­molecular O—H⋯O hydrogen bond occurs between the hydroxyl group and the central carboxyl­ate group of the citrate anion as well as a charge-assisted inter­molecular O—H⋯O link between the water mol­ecule and the terminal carboxyl­ate group. There is also a weak C—H⋯O hydrogen bond.