We previously reported the probable gas phase decomposition mechanism of tetraneopentyl zirconium (ZrNp4) under typical MOCVD (metalorganic chemical vapor deposition) conditions (400 to 800 ℃) using computational thermochemistry. By the same approach, we performed a mechanistic study of the gas phase decomposition of trineopentyl zirconium monochloride (ZrNp3Cl) to evaluate its possibility as a CVD precursor for ZrC film growth. It was demonstrated that strong Zr-Cl bonding would require much higher growth temperatures to drive the gas phase decomposition of ZrNp3Cl, compared to ZrNp4. The higher temperature growth would pose the problem of accelerated gas phase parasitic reactions, which potentially hamper ZrC deposition on the surface. However, strong Zr-Cl bonding offers the possibility of ZrC ALD (atomic layer deposition) using dineopentyl zirconium dichloride (ZrNp2Cl2), and a postulated scheme is presented based on the results from the gas phase decomposition study of ZrNp4 and/or ZrNp3Cl.