A composition can include a Rho zeolite with a RHO topology having a Si to B ratio or a Si to Al ratio greater than or equal to 8. Making such a composition can include heating an aqueous reaction mixture having a molar ratio of atomic Si to atomic B of about 4 to about 50 or a molar ratio of atomic Si to atomic Al of about 4 to about 50 in the presence of a C4-C6 diquat of N,2-dimethylbenzimidazole structure directing agent to a temperature of at least 75° C. to produce a Rho zeolite.