{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T16:29:47Z","timestamp":1781281787482,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2024,7,19]],"date-time":"2024-07-19T00:00:00Z","timestamp":1721347200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DIUFRO Project","award":["DI23-0026"],"award-info":[{"award-number":["DI23-0026"]}]},{"name":"DIUFRO Project","award":["ECM-02"],"award-info":[{"award-number":["ECM-02"]}]},{"name":"DIUFRO Project","award":["TKII-E-0424-I-090424-20\/PR-22"],"award-info":[{"award-number":["TKII-E-0424-I-090424-20\/PR-22"]}]},{"name":"DIUFRO Project","award":["1230055"],"award-info":[{"award-number":["1230055"]}]},{"name":"DIUFRO Project","award":["AFB220001"],"award-info":[{"award-number":["AFB220001"]}]},{"name":"NLHPC","award":["DI23-0026"],"award-info":[{"award-number":["DI23-0026"]}]},{"name":"NLHPC","award":["ECM-02"],"award-info":[{"award-number":["ECM-02"]}]},{"name":"NLHPC","award":["TKII-E-0424-I-090424-20\/PR-22"],"award-info":[{"award-number":["TKII-E-0424-I-090424-20\/PR-22"]}]},{"name":"NLHPC","award":["1230055"],"award-info":[{"award-number":["1230055"]}]},{"name":"NLHPC","award":["AFB220001"],"award-info":[{"award-number":["AFB220001"]}]},{"name":"IPICYT Supercomputing National Center","award":["DI23-0026"],"award-info":[{"award-number":["DI23-0026"]}]},{"name":"IPICYT Supercomputing National Center","award":["ECM-02"],"award-info":[{"award-number":["ECM-02"]}]},{"name":"IPICYT Supercomputing National Center","award":["TKII-E-0424-I-090424-20\/PR-22"],"award-info":[{"award-number":["TKII-E-0424-I-090424-20\/PR-22"]}]},{"name":"IPICYT Supercomputing National Center","award":["1230055"],"award-info":[{"award-number":["1230055"]}]},{"name":"IPICYT Supercomputing National Center","award":["AFB220001"],"award-info":[{"award-number":["AFB220001"]}]},{"name":"Chilean sources Fondecyt","award":["DI23-0026"],"award-info":[{"award-number":["DI23-0026"]}]},{"name":"Chilean sources Fondecyt","award":["ECM-02"],"award-info":[{"award-number":["ECM-02"]}]},{"name":"Chilean sources Fondecyt","award":["TKII-E-0424-I-090424-20\/PR-22"],"award-info":[{"award-number":["TKII-E-0424-I-090424-20\/PR-22"]}]},{"name":"Chilean sources Fondecyt","award":["1230055"],"award-info":[{"award-number":["1230055"]}]},{"name":"Chilean sources Fondecyt","award":["AFB220001"],"award-info":[{"award-number":["AFB220001"]}]},{"name":"CEDENNA","award":["DI23-0026"],"award-info":[{"award-number":["DI23-0026"]}]},{"name":"CEDENNA","award":["ECM-02"],"award-info":[{"award-number":["ECM-02"]}]},{"name":"CEDENNA","award":["TKII-E-0424-I-090424-20\/PR-22"],"award-info":[{"award-number":["TKII-E-0424-I-090424-20\/PR-22"]}]},{"name":"CEDENNA","award":["1230055"],"award-info":[{"award-number":["1230055"]}]},{"name":"CEDENNA","award":["AFB220001"],"award-info":[{"award-number":["AFB220001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>(TiO2) is both a natural and artificial compound that is transparent under visible and near-infrared light. However, it could be prepared with other metals, substituting for Ti, thus changing its properties. In this article, we present density functional theory calculations for Ti(1\u2212x)AxO2, where A stands for any of the eight following neutral substitutional impurities, Fe, Ni, Co, Pd, Pt, Cu, Ag and Au, based on the rutile structure of pristine TiO2. We use a fully unconstrained version of the density functional method with generalized gradient approximation plus the U exchange and correlation, as implemented in the Quantum Espresso free distribution. Within the limitations of a finite-size cell approximation, we report the band structure, energy gaps and absorption spectrum for all these cases. Rather than stressing precise values, we report on two general features: the location of the impurity levels and the general trends of the optical properties in the eight different systems. Our results show that all these substitutional atoms lead to the presence of electronic levels within the pristine gap, and that all of them produce absorptions in the visible and near-infrared ranges of electromagnetic radiation. Such results make these systems interesting for the fabrication of solar cells. Considering the variety of results, Ni and Ag are apparently the most promising substitutional impurities with which to achieve better performance in capturing the solar radiation on the planet\u2019s surface.<\/jats:p>","DOI":"10.3390\/nano14141224","type":"journal-article","created":{"date-parts":[[2024,7,19]],"date-time":"2024-07-19T13:12:57Z","timestamp":1721394777000},"page":"1224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Effect of Substitutional Metallic Impurities on the Optical Absorption Properties of TiO2"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1705-6196","authenticated-orcid":false,"given":"Eduardo","family":"Cisternas","sequence":"first","affiliation":[{"name":"Departamento de Ciencias F\u00edsicas, Universidad de La Frontera, Casilla 54-D, Temuco 4811230, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodrigo","family":"Aguilera-del-Toro","sequence":"additional","affiliation":[{"name":"Departamento de F\u00edsica Te\u00f3rica, At\u00f3mica y \u00d3ptica, Universidad de Valladolid, 47011 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8925-3180","authenticated-orcid":false,"given":"Faustino","family":"Aguilera-Granja","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica, Universidad Aut\u00f3noma de San Luis Potos\u00ed, San Luis Potos\u00ed 78295, Mexico"},{"name":"Donostia International Physics Center (DIPC), 20018 San Sebastian, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenio E.","family":"Vogel","sequence":"additional","affiliation":[{"name":"Departamento de Ciencias F\u00edsicas, Universidad de La Frontera, Casilla 54-D, Temuco 4811230, Chile"},{"name":"Facultad de Ingenier\u00eda, Universidad Central de Chile, Santiago 8330601, Chile"},{"name":"Centro Para el Desarrollo de la Nanociencia y la Nanotecnolog\u00eda (CEDENNA), Santiago 7170124, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.saa.2012.01.011","article-title":"Fungus-mediated biosynthesis and characterization of TiO2 nanoparticles and their activity against pathogenic bacteria","volume":"91","author":"Rajakumar","year":"2012","journal-title":"Spectrochim. 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