Photoswitch triads comprising two dihydroazulene (DHA) units in conjugation with a central trans‐azobenzene (AZB) unit were prepared in stepwise protocols starting from meta‐ and para‐disubstituted azobenzenes. The para‐connected triad had significantly altered optical properties and lacked the photoactivity of the separate photochromes. In contrast, for the meta‐connected triad, all three photochromes could be photoisomerized to generate an isomer with two vinylheptafulvene (VHF) units and a cis‐azobenzene unit. Ultrafast spectroscopy of the photoisomerizations revealed a fast DHA‐to‐VHF photoisomerization and a slower trans‐to‐cis AZB photoisomerization. This meta triad underwent thermal VHF‐to‐DHA back‐conversion with a similar rate of all VHFs, independent of the identity of the neighboring units, and in parallel thermal cis‐to‐trans AZB conversion. The experimental observations were supported by computation (excitation spectra and orbital analysis of the transitions).
In this paper, we derive alternative cluster perturbation series to the energy cluster perturbation (ECP) series of Paper I. The ECP series were derived using the standard coupled cluster energy framework. Here, we use the coupled cluster Lagrangian framework to derive the Lagrangian cluster perturbation (LCP) series and show that a slightly modified order concept means that the ECP and the LCP series become identical. Using the Lagrangian, we also derive a perturbation series where total cluster amplitudes and multipliers are determined through the same orders as dictated by the 2n+1/2n+2 rule, the VCP series. The VCP energies have errors that are bilinear in the errors of the total cluster amplitudes and multipliers. Test calculations have been performed for S(D) and SD(T) orbital excitation spaces. The convergence of the test calculations can be divided into two groups. The first group contains molecules that exhibit a slow monotonic geometric convergence pattern in both orbital spaces. The second group, containing the rest of the molecules, exhibits a fast low order convergence. For the S(D) calculations, the deviations in fourth order from the coupled cluster singles and doubles energy are below 1.3 per cent for the LCP series and 0.3 per cent for the VCP series, respectively. For the SD(T) calculations, the second group hardly shows any difference between the low order convergence of the three series ECP, LCP, and LCP and at fourth order the deviations from the triples correlation energy are less than 1 per cent.
In this paper, we present an investigation concerning the prospects of using nanoparticles to improve solar energy storage properties of three different norbornadiene/quadricyclane derivatives. Computationally, we study how different nanoparticles...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.