RESUMO
Chlorination of CS2 leads to trichloromethanesulfenyl chloride, Cl3 CSCl, in moderate yields. The oxidation of Cl3 CSCl with H2 O2 gives Cl3 CSO2 Cl, the chloride of trichloromethanesulfonic acid. Cl3 CSO2 Cl is the crucial product for the preparation of trichloromethanesulfonates ("trichlates") and has been characterized by IR spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction measurements (P-1, a=609.99(5) pm, b=727.45(6) pm, c=782.49(7) pm, α=80.644(3)°, ß=85.175(3)°, γ=88.311(3)°. The acid Cl3 CSO3 H can be gained in form of the hydrate (H5 O2 )[Cl3 CSO3 ] in two different modifications (I: monoclinic, P21 /n, Z=8, a=1292.47(7) pm, b=605.89(2) pm, c=2661.1(1) pm, ß=98.708(4)°, V=1672.8(1) Å3 ; II: monoclinic, Cc, Z=4, a=699.80(5) pm, b=1054.72(8) pm, c=1139.88(8) pm, ß=95.303(3)°, V=837.7(1) Å3 . Both modifications have been investigated by IR spectroscopy, thermal analyses and theoretical calculations.
RESUMO
Double-rough surfaces were prepared by using mixtures of metal oxide nanoparticles with diameters on two different length scales. The degree of double-roughness of these surfaces was controlled using defined ratios of larger (approximately 300 nm) and smaller (approximately 30 nm) particles. If the preparation method was chosen such that the smaller particles decorate the larger ones, a roughness on two length scales was induced and an increase of contact angles from 130 degrees to 160 degrees with increasing double-roughness was observed. At highest double-roughness, a transition from the Wenzel to Cassie regime occurred. The results were quantitatively modeled on the basis of a modified Wenzel equation taking into account the two hierarchies of roughness.