“…5). Such huge contrast behaviors between the TPE-based inhibitors and raw materials could be understood from two aspects: (1) hard and so acids and bases (HSAB) theory; 46,47 (2) synergistic effect of the charged ingredients of the inhibitors. 5,48,49 According to HSAB theory, Fe atom is classied as a so Lewis acid with vacant electron orbitals, while thiocyanate anion (SCN − ) is categorized as a so Lewis base which is abundant with p electrons and lone pair electrons.…”