Using a Morse type pair potential, molecular-dynamics simulations have been performed to investigate the atomic geometries, growing patterns, structural stabilities, energetics and magic sizes of T-n, V-n and Cr-n (n = 2-50) clusters. Following rearrangement collision of the atom-cluster system in fusion process, and absorbing their energies step by step down to 0K, possible optimal equilibrium geometries of the clusters have been generated to tackle the structural determination problem. This approach serves an efficient alternative to the growing path identification and the optimization techniques. It has been found that titanium, vanadium and chromium clusters prefer to form three-dimensional compact structures in the determined configurations and the appearances of medium sizes are, in general, five-fold symmetry on the spherical clusters. Moreover, relevant relations between atomic arrangements in the clusters and the magic sizes have been observed.