In the present work, three dyes of 6,7-dihydroxy-8-[(E)-(4-methoxyphenyl)diazenyl]-4-methyl-2Hchromen-2-one, (D1) 6,7-dihydroxy-8-[(E)-(4-hydroxyphenyl) diazenyl]-4-methyl-2H-chromen-2-one
(D2), and 6,7-dihydroxy-4-methyl-8-[(E)-(4-methylphenyl) diazenyl]-2H-chromen-2-one (D3) were
experimentally tested as photosensitizer in solar cell. and a computation study was conducted to explain
the efficiency of these compounds as photo-sensitizer in a solar cell. The polarizability ( ), the anisotropy of the polarizability ( ), ground-state dipole moment (m) and the first-order hyperpolarizability (b) of the dyes were studied at Density Functional Theory (DFT) using Gaussian 09 and Gauss View
v.6.0 based on keywords: ‘‘opt freq b3lyp/6-311G++(d,p) guess = mix pop=(nbo, savenbos) geom = connectivity polar = optrot. Also, EHOMO (the highest occupied molecular orbital energy), ELUMO (the lowest unoccupied molecular orbital energy), HOMO-LUMO energy gap (DE), electron affinity (A), and ionization
potential are investigated. The calculation based on the structure modification of the dyes with
electron-withdrawing groups (HO-C and CH3-O-C) and electron repelling group (H3C-C) based on a
push-pull framework of Qumarin was studied. The simulations indicate that the improvement of
Qumarin-based dyes can reduce the energy gap and produce a redshift. This structural modification also
improves the light-capturing and the electron injection capability, making it excellent in photoelectric
conversion efficiency (PCE). This structural modification also improves the light-capturing and the electron injection capability, making it excellent in photoelectric conversion efficiency (PCE).

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