  We have successfully synthesized S = 1/2 kagome antiferromagnets MCu3(OH)6Cl2
(M = Ni and Co) by hydrothermal method with rotating pressure vessel.
Structural characterization shows that both compounds have the similar crystal
structure as ZnCu3(OH)6Cl2 with R-3m symmetry. Similar to ZnCu3(OH)6Cl2, the
compounds show no obvious hysteresis at 2 K. A spin glass transition is found
in both NiCu3(OH)6Cl2 and CoCu3(OH)6Cl2 at low temperatures (6.0 and 3.5 K
respectively) by AC susceptibility measurements. It indicates no long-range
magnetic order and a strong spin frustration. The substitution of Zn2+ by
magnetic ions Ni2+ or Co2+, effectively enhances interlayer exchange coupling
and changes the ground state of the kagome spin system.
