Design and Color Prediction of Anthracene-Based Dyes Based on Quantum Chemical Calculations

TL;DR

This paper uses quantum calculations to predict the colors of anthracene-based dyes and provides a model for designing new pigments with high efficiency.

Contribution

The study introduces a computational model linking quantum calculations to color prediction for anthracene derivatives.

Findings

Frontier molecular orbital analysis showed an inverse correlation between conjugation extent and HOMO-LUMO energy gap.

TD-DFT calculations predicted excitation wavelengths of 438 nm, 441 nm, 464 nm, and 496 nm for four anthracene derivatives.

Complementary color theory predicted visual colors of yellow, yellow, red, and orange based on absorption characteristics.

Abstract

We systematically investigated the parent anthracene (abbreviated as en-1, C14H10) and three N,N′-disubstituted derivatives: the 1,5-diethylanthracene (en-2, C18H18), the 1,5-divinylanthracene (en-3, C18H14), and the 1,5-diphenylanthracene (en-4, C26H18), using a rigorous density functional theory (DFT)/time-dependent density functional theory (TD-DFT) approach. Following full geometric optimization and frequency validation (no imaginary frequencies), frontier molecular orbital analysis revealed an inverse correlation between conjugation extent and the HOMO-LUMO energy gap. Electrostatic potential (ESP) analysis further indicated a progressive increase in surface potential variance upon substitution, reflecting charge redistribution. TD-DFT calculations yielded vertical excitation wavelengths of 438 nm, 441 nm, 464 nm, and 496 nm for en-1, en-2, en-3, and en-4, respectively. Complementary color theory predicts visual colors of yellow, yellow, red, and orange for these compounds based on their absorption characteristics. This work establishes a closed-loop “computation-spectra-color” model for anthracene-based dyes, providing a transferable design paradigm for novel functional pigments with high molar extinction coefficients.

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