Crystal structure of dirubidium hydrogen citrate from laboratory X-ray powder diffraction data and DFT comparison
Alagappa Rammohan1, James A Kaduk2
1Atlantic International University, Honolulu, HI, USA.
Abstract:
The crystal structure of dirubidium hydrogen citrate, 2Rb+·HC6H5O72-, has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The un-ionized carb-oxy-lic acid group forms helical chains of very strong hydrogen bonds (O⋯O ∼ 2.42 Å) along the b axis. The hy-droxy group participates in a chain of intra- and inter-molecular hydrogen bonds along the c axis. These hydrogen bonds result in corrugated hydrogen-bonded layers in the bc plane. The Rb+ cations are six-coordinate, and share edges and corners to form layers in the ab plane. The inter-layer contacts are composed of the hydro-phobic methyl-ene groups.
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