The possibility of formation for a bound state of a $t$ quark and a lighter one is investigated using potential model predictions and heavy quark effective theory approach. Resulting estimates for the 1S--2S splitting of the energy levels are compared to the total top decay width $��_t$ . As for the case of toponium, our conclusions show that the probability of formation for T-mesons is negligibly small due to the high top mass value.

14 pages, 3 figures, epsfig macro