Triafulvalene is a compound of immense theoretical applications, having a planar geometry of D2h symmetry, with two three-member rings consisting of an endocyclic double bonds in each ring and an exocyclic double bond common to both rings. The paper presents the result of a theoretical study on the effect of functional groups on λmax of triafulvalene. The molecules used in the study are triafulvalene, mono substituted triafulvalene where the substitutents are -C2H4, -CHO, -OH, -CN, -NH2, -NO2

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... d -Cl; di tri and tetra substituted fulvalenes, where the substituents are -C2H4 and -NO2. The correlation between HOMO-LUMO gap and bond lengths with λmax is analyzed in detail for vinyl and cyano substituents. Geometries are optimised using PBEPBE functional using 6-311++G (2d,p) basis sets and to generate the electronic energy states and UV-Visible data Time Dependent Density Functional Theory studies are performed using the same theoretical level. Studies shows that functionasl groups with multiple bonds increases the absorption maximum and in the case of multi substituted systems, the absorption maxima depends on the HOMO-LUMO gap.