{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T01:33:58Z","timestamp":1790386438933,"version":"4.1.0"},"reference-count":55,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2017,6,30]],"date-time":"2017-06-30T00:00:00Z","timestamp":1498780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The effects of Mg, Zn, Cd, and Pd dications on the photophysical properties of the tetraphenylporphyrin ligand have been explored, considering the corresponding complexes and by using the density functional theory and its time-dependent extension. Results show that absorption wavelengths do not change significantly when the metal ion changes contrary to what happens to the singlet\u2013triplet energy gaps (\u0394ES\u2212T) and the spin-orbit matrix elements \u03a8SnHso\u03a8Tm. The most probable intersystem spin crossing (ISC) pathways for the population of the lowest triplet states have been explored. Our findings can contribute to rationalize the available experimental data and promote the potential therapeutic use of these compounds as photosensitizers in photodynamic therapy (PDT).<\/jats:p>","DOI":"10.3390\/molecules22071093","type":"journal-article","created":{"date-parts":[[2017,6,30]],"date-time":"2017-06-30T10:04:58Z","timestamp":1498817098000},"page":"1093","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":54,"title":["Metal Atom Effect on the Photophysical Properties of Mg(II), Zn(II), Cd(II), and Pd(II) Tetraphenylporphyrin Complexes Proposed as Possible Drugs in Photodynamic Therapy"],"prefix":"10.3390","volume":"22","author":[{"given":"Bruna Clara De","family":"Simone","sequence":"first","affiliation":[{"name":"Dipartimento di Chimica e Tecnologie Chimiche, Universit\u00e0 della Calabria, I-87036 Arcavacata di Rende, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4686-6876","authenticated-orcid":false,"given":"Gloria","family":"Mazzone","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica e Tecnologie Chimiche, Universit\u00e0 della Calabria, I-87036 Arcavacata di Rende, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nino","family":"Russo","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica e Tecnologie Chimiche, Universit\u00e0 della Calabria, I-87036 Arcavacata di Rende, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilia","family":"Sicilia","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica e Tecnologie Chimiche, Universit\u00e0 della Calabria, I-87036 Arcavacata di Rende, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marirosa","family":"Toscano","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica e Tecnologie Chimiche, Universit\u00e0 della Calabria, I-87036 Arcavacata di Rende, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1002\/wcms.83","article-title":"Spin-orbit coupling and intersystem crossing in molecules","volume":"2","author":"Marian","year":"2012","journal-title":"Wiley Interdiscip. 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