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Through a combination of photoluminescence measurements, high-angle annular dark-field scanning transmission electron microscopy analysis, and an Ising model based physical vapor-deposition simulation, we show that higher PDM of tris[2-phenylpyridinato-C2,N]iridium(III) guest can actually lead to a reduced aggregation relative to tris[bis[2-(2-pyridinyl-N)phenyl-C] (acetylacetonato)iridium(III) when doped into a non-polar host 1,3,5-tris(carbazol-9-yl)benzene. This study further explores the effect of host polarity by using a polar host 3\u2032,5\u2032-di(carbazol-9-yl)-[1,1\u2032-biphenyl]-3,5-dicarbonitrile, and it is shown that the polar host leads to reduced guest aggregation. This study provides a comprehensive understanding of the impact of molecular PDM on OLED material efficiency and stability, providing insights for optimizing phosphorescent OLED materials.<\/jats:p>","DOI":"10.1063\/5.0201560","type":"journal-article","created":{"date-parts":[[2024,6,24]],"date-time":"2024-06-24T12:10:29Z","timestamp":1719231029000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":6,"title":["Effect of molecular permanent dipole moment on guest aggregation and exciton quenching in phosphorescent organic light emitting diodes"],"prefix":"10.1063","volume":"160","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9569-5284","authenticated-orcid":false,"given":"Paul","family":"Niyonkuru","sequence":"first","affiliation":[{"name":"Department of Physics, Colorado School of Mines 1 , Golden, Colorado 80401, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roland A.","family":"Bennett","sequence":"additional","affiliation":[{"name":"Department of Physics, Colorado School of Mines 1 , Golden, Colorado 80401, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1910-1357","authenticated-orcid":false,"given":"Michael J.","family":"Zachman","sequence":"additional","affiliation":[{"name":"Center for Nanophase Materials Sciences, Oak Ridge National Laboratory 2 , Oak Ridge, Tennessee 37831, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8936-5345","authenticated-orcid":false,"given":"Jeramy D.","family":"Zimmerman","sequence":"additional","affiliation":[{"name":"Department of Physics, Colorado School of Mines 1 , Golden, Colorado 80401, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2024,6,24]]},"reference":[{"key":"2024062411425082100_c1","doi-asserted-by":"publisher","first-page":"151","DOI":"10.1038\/25954","article-title":"Highly efficient phosphorescent emission from organic electroluminescent devices","volume":"395","year":"1998","journal-title":"Nature"},{"key":"2024062411425082100_c2","doi-asserted-by":"publisher","first-page":"124314","DOI":"10.1063\/1.3480981","article-title":"Sensitivity of the photophysical properties of organometallic complexes to small chemical changes","volume":"133","year":"2010","journal-title":"J.\u00a0Chem. 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