Hybrid molecular system of acetylide and thiourea generally provide a wide range of electronic properties as they exhibit electronic delocalization in extended like-rod rigid π-orbital molecular system in their designated molecular framework. In this occasion, a new member of 4-methylbenzoyl-3-(4-ethynylbenzonitrile-phenyl)-thiourea (MeCNTh) was successfully designed, synthesised, and characterised for semiconductor properties and interest. The preliminary response of MeCNTh towards CO2 gas was evaluated via density functional theory (DFT) at B3LYP/6-31G (d,p) TD-SCF level of theory. The unique properties of MeCNTh is attributed by the presence of two potential active site of -NH-C=O and acetylide C≡C for H-bonding interaction between molecule MeCNTh and CO2 analyte. The sensing behaviors of both active sites were evaluated in term of interaction and stabilisation energy that give an effective evidence for sensing ability between MeCNTh and CO2. In fact, the response of sensing properties was also obtained from the difference in Mulliken charge distribution of MeCNTh and MeCNTh-CO2 to provide mechanism response of MeCNTh and CO2. Results revealed that -NH-C=O site of MeCNTh is a good interaction site for MeCNTh-CO2 to occur.
