Metallic nanoparticles, especially transition metals, have outstanding optical, electrical, magnetic and chemical properties. Synthesis of metallic nanoparticles and their experimental investigation is not an easy work and hence, simulation studies to estimate their properties can be very important. In the present work, x-ray powder diffraction pattern (XRD) of titanium metallic quantum dots with hexagonal crystal structure is computationally simulated. There are two identified crystal structure for titanium metal: one with body centered cubic (BCC) structure and the other with hexagonal closed packed (hcp) structure. At the ambient normal conditions of pressure and temperature, the hcp structure is more stable than BCC one. For this trigonal symmetry the lattice constants are a=b=2.95Å and c=4.68Å. Each primitive unit cell includes two titanium atoms with coordinates Ti_1=(0,0,0) and Ti_2=(a/√3Cos(30),a/√3 Sin(30),c/2). To simulate x-ray diffraction of Ti nanoparticles, a computer code is developed by the authors. In the home-made computer code, the original formulation of light diffraction is used which is very more general than the Bragg diffraction formulation.
