scatter
渙 centers on scattering or dispersing, like water spreading out and dissolving something into a wider area.
渙 combines 氵 (water) with 奐, which likely contributes the sound and the idea of spreading or expanding. The exact historical development of 奐 is uncertain.
Water 氵 plus a spreading shape 奐: imagine water flowing outward and scattering in all directions, like ripples dispersing on a pond.
For カン, picture a can of water being kicked over, scattering its contents everywhere: can -> カン, and the water scatters.