We report on a systematic study of the experimental parameters to control size and morphology of half metals Heusler nanoparticles synthesized by pulsed laser deposition (PLD) technique. Our findings suggest the existence of a threshold across which the mechanism of particle growth changes: core-shell NPs for higher values of laser energy and randomic amorphous structure for lower values of laser energy. The growth mechanisms are discussed in deep based on the high resolution transmission electron microscopy (HR-TEM) results; and a phase diagram was developed to summarize our findings. (C) 2017 Published by Elsevier B.V.