Based on the influence of lithium content in some optical materials to the structure stability and optical proterties,the structure stablility and vibration spectroscopy of carbon-doped clusters LinC(n=1~9) were investigated with density functional theory at the B3LYP/6-31G(d) level.The computed results shown that the structure were three dimension(n>3) structure for LinC except for Li2C and the carbon atom was seen to be trapped in a Li cage.Especially,the electron ground state was found to be a low state for LinC cluster,singlet for n is even while doublet for n is odd.A strong even-odd alternation in the cluster stability appeared in the incremental binding energy,with their n-even numbers being much more stable than the adjacent odd-numbered ones.These parity effects also appeared in the second difference in energy and the gap between HOMO-LUMO.In addition,the dominant channel was losing a Li particle for LinC clusters by analyzing the fragmentation energies.The spectroscopy range of LinC clusters located in fingering area.The vibration frequency of LinC clusters decreased with the increasing of the numbers of Lithium atoms.Moreover,the difference between the lowest and the highest vibration frequency shown maxmium as the number of lithium atoms was odd while it shown minimum as the number of lithium atoms was even.