SEMIEMPIRICAL STUDY ON ELECTRONICAL TRANSITION SPECTRA OF ETHYL PMETHOXYCINNAMATE (EPMS) FROM KENCUR (KAEMPFERIA GALANGA) FOR SUNSCREEN COMPONENT

Abstract

ABSTRAK Telah dilakukan analisis in silico senyawa tabir surya Etil Para Metoksi Sinamat (EPMS) berdasarkan data transisi elektronik molekul senyawa yang bertujuan untuk memperkirakan EPMS sebagai senyawa tabir surya perisai alami UV-B. Kajian dilakukan dengan membuat model molekul senyawa tabir surya standar Isopropil Para Metoksi Sinamat (IPMS) yang dioptimasi geometri menggunakan metode semiempirik AM1 dan dilanjutkan optimasi analisis spektra transisi elektronik dengan metode ZINDO/S, ZINDO 1, PM3, dan AM1. Analisis spektra transisi elektronik difokuskan pada UV-B (290-315 nm). Hasil kajian secara umum menunjukkan analisis spekta transisi elektronik terbaik adalah ZINDO/s. Perhitungan dengan metode ZINDO/S pada IPMS menunjukkan λ max yaitu 290,77 nm dan senyawa EPMS diperoleh nilai λ max 292,41 nm. Hasil ini menunjukkan bahwa EPMS dapat dimanfaatkan sebagai perisai alami UV-B. Kata Kunci : tabir surya, transisi elektronik, EPMS, IPMS, AM1, ZINDO/S ABSTRACT In silico analysis of sunscreen compound, Ethyl p-methoxycinnamate, has been done. The aim of the study is to estimate Ethyl p-methoxycinnamate (EPMS) as sunscreen compound or as a natural shield UV-B. The calculation procedure was done as geometry structure optimization on Isopropyl p-methoxycinnamate (IPMS) as standard sunscreen compound by semiempirical method, AM1 and followed by optimized electronic transition spectral analysis that was calculated by ZINDO/S, ZINDO 1, PM3, and AM1. Analysis of the theoretical spectra was focused in the UV-B (290-315 nm). The results of study showed that the best electronic spectral analysis was ZINDO/S. The electronic transition spectra of IPMS give λ max 290.77 nm and EPMS give λ max 292.41 nm. These results indicate that the EPMS could be utilized as sunscreen compound of UV-B.