Isomerization for photochemical solar energy storage

Abstract

An invention relating to photochemical collection, storage, and retrieval of solar energy through exposing to solar energy in the visible light spectrum of a photochemical valence isomerizable composition for a time converting a significant portion thereof to an intramolecular strained ring structure of higher energy content, retaining the higher energy content intramolecular strained ring structure until energy release is desired therefrom, and subsequently initiating conversion of the higher energy content intramolecular strained ring structure to its initial molecular structure through application of heat and/or catalyst thereto with a resultant exothermic conversion releasing heat in excess of that requisite for initiating and continuing the conversion and with the heat in excess thereof available for useful thermal applications; in the preferred method embodiment employing an organic valence isomerizable compound of a structure which includes two reactive carbon-to-carbon double bonds oriented in relation to each other such as to cyclize intramolecularly to the intramolecular strained ring structure upon exposure to solar radiation of a wavelength between 350 and 800 nm through the employed valence isomerizable compound including in its structure at least one chromophoric moiety from the group consisting of dihydroparaquinone moieties, orthoquinone moiety, trans- and cis-.beta.-aminoenone moieties, and moiety mixtures thereof with inclusion of said moieties in an amount providing maximum light absorbance between 350 and 800 nm for said valence isomerizable compound; and various novel compounds employed in the preferred method.