The lowest singlet and tripler electronic states of CuH3, AgH3, and AuH3 were studied. The molecular parameters were optimized at the coupled cluster:singles doubles level augmented with perturbative correction for connected triple excitation (CCSD(T)). The equilibrium geometric structures of the lowest Singlet states are Y-shaped, with very small values for the valence H-M-H angle. The T-Shaped and linear conformations are found to be transition structures. The electronic density and vibrational mode analysis indicates that these molecules can be considered as adducts of a H-2 molecule to the corresponding monohydrides: The lowest triplet states lie similar to 25 000-29 000 cm(-1) above the minimum of the singlet state.;The equilibrium geometry structures of the lowest triplet states are pyramidal with small inversion barriers.