Two new compounds, Rb 2 (HSO 4 )(H 2 PO 4 ) and Rb 4 (HSO 4 ) 3 (H 2 PO 4 ), were synthesized from aqueous solutions of RbHSO 4 /RbH 2 PO 4 . The compounds were characterized by Xray single crystal analysis and neutron powder di4raction. For Rb 2 (HSO 4 )(H 2 PO 4 ), room temperature and a low temperature modi5cation were found. According to X-ray crystal structure analysis, the compounds have the following crystal data:
3 , Z โซุโฌ 2, R 1 โซุโฌ 0.033; Rb 2 (HSO 4 )(H 2 PO 4 ) (T โซุโฌ 160K), monoclinic, space group P2 1 /c, a โซุโฌ 11.555(3) A > , b โซุโฌ 7.536(2) A > , c โซุโฌ 9.593(2) A > , โซุโฌ 91.56(2)3, V โซุโฌ 853.0(4) A > 3 , Z โซุโฌ 4, R 1 โซุโฌ 0.041; Rb 4 (HSO 4 ) 3 (H 2 PO 4 ), orthorhombic, space group P2 1 2 1 2, a โซุโฌ 7.612(6) A > , b โซุโฌ 14.795(9) A > , c โซุโฌ 7.446(4) A > , V โซุโฌ 838.6(9) A > 3 , Z โซุโฌ 2, R 1 โซุโฌ 0.045. The compounds have di4erent coordination numbers of rubidium, being 7, 8, 9, or 10 with Rb+O distances from 2.9 to 3.3 A > . In all cases there were di7culties in the allocation of sulfur and phosphorus due to the small di4erences in their radii and scattering factors. All structures are characterized by HSO ุ 4 and H 2 PO ุ 4 , or disordered H x S/PO ุ 4 tetrahedra connected to zigzag chains via hydrogen bridges. These chains are linked by additional hydrogen bonds to a layer-like hydrogen bonding system.