Density Functional Theory Calculations of Hydroxyapatite Biological Materials

Crystal structure of atomic-scale hydroxyapatite and electronic structure is characterized by means of Density Functional Calculation.The results show that hydroxyapatite is P63 space group for the six-party cell.Lattice parameters are a=0.9302nm,b=0.9303nm,c=0.6770nm,α=90o,β=90o and γ=120o.Total density of states is mainly composed of atomic s,p,d states and fermi level is mainly contributed by oxygen 2p4 orbit.The results also show that the oxygen 2p electron is the liveliest in a single cell.Comparing the optimized diffraction pattern with experimental one,they are well-matched.