Figure 5From: Synthesis, structure and solvatochromic properties of some novel 5-arylazo-6-hydroxy-4-phenyl-3-cyano-2-pyridone dyes The most stable azo (A) and hydrazone (B) tautomer optimized structures of dye 1, at the B3LYP/6-31G(d) level of theory. Back to article page