title: A theoretical study of the UV absorption of 4-methylbenzylidene camphor: from the UVB to the UVA region.
abstract: In this study, a theoretical approach was used to study the UV absorption of the UVB filter, 4-methylbenzylidene camphor. The main objective of this work was to design new UVA filters based on this rather photo-stable compound, so that photo-degradation in this UV region can be avoided without the use of other molecules. This objective was achieved by the simultaneous addition of two appropriate substituents, which led to red-shifts of up to 0.69 eV while maintaining appreciable oscillator strength. Also, useful structure-energy relationships were derived, which allow for the development of more UVA filters based on 4-methylbenzylidene camphor.
authors.affiliation: Centro de Investigação em Química, Departamento de Química e Bioquímica, Faculdade de Ciência, Universidade do Porto, s/n, 4169-007, Porto, Portugal. jcsilva@fc.up.pt.
authors.forename: Luís Pinto
authors.initials: LP
authors.lastname: da Silva
authors.forename: Paulo J O
authors.initials: PJ
authors.lastname: Ferreira
authors.forename: Margarida S
authors.initials: MS
authors.lastname: Miranda
authors.forename: Joaquim C G
authors.initials: JC
authors.lastname: Esteves da Silva