{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T21:59:42Z","timestamp":1771883982116,"version":"3.50.1"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":0,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Accurate and simple determination of key photophysical parameters, such as triplet quantum yield and intersystem crossing rate, holds significant technological importance for a series of modern biologics, optics, and photonics applications, such as near-infrared imaging, photodynamic therapy, and photocatalysis. Techniques such as double- or multi-pulse fluorescence (DPF or MPF) excitation allow for the measurement of some of these parameters even for molecules with 0.1% fluorescence quantum yield on the ns regime. In addition, these techniques only require knowledge of the molecules\u2019 fluorescence lifetime when properly modeled. In this scenario, we have built a novel noncollinear DPF technique, which is advantageous for constructing DPF setups with any ultrafast-pulsed laser system. We demonstrate that this noncollinear configuration produces results equivalent to the traditional collinear setup using a newly adapted model for fitting the data. Hence, we develop a framework for performing DPF experiments in both collinear and noncollinear geometries using two models, which consider either a flat-top or a Gaussian beam profile. Our findings show that under optical saturation, both models yield the same results; however, considering a Gaussian beam profile, one allows for triplet quantum yield determination at lower laser fluence values due to the closer proximity to the experimental laser beams used. The new setup was demonstrated on a new class of recently synthesized cationic porphyrins, for which no previous photophysical characterization has been made.<\/jats:p>","DOI":"10.2139\/ssrn.6257408","type":"posted-content","created":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T21:02:57Z","timestamp":1771880577000},"source":"Crossref","is-referenced-by-count":0,"title":["Triplet quantum yield determination with noncollinear double pulse fluorescence applied to a new class of cationic free-based porphyrins"],"prefix":"10.2139","author":[{"given":"Rafael  de Queiroz","family":"Garcia","sequence":"first","affiliation":[]},{"given":"Leandro  H. Zucolotto","family":"Cocca","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9373-7006","authenticated-orcid":true,"given":"Nuno M. M.","family":"Moura","sequence":"additional","affiliation":[]},{"given":"M.  Amparo F.","family":"Faustino","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6672-2186","authenticated-orcid":true,"given":"Cleber  R.","family":"Mendonca","sequence":"additional","affiliation":[]},{"given":"Leonardo","family":"De Boni","sequence":"additional","affiliation":[]}],"member":"78","container-title":[],"original-title":[],"deposited":{"date-parts":[[2026,2,23]],"date-time":"2026-02-23T21:02:57Z","timestamp":1771880577000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ssrn.com\/abstract=6257408"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026]]},"references-count":0,"URL":"https:\/\/doi.org\/10.2139\/ssrn.6257408","relation":{},"subject":[],"published":{"date-parts":[[2026]]},"subtype":"preprint"}}