1. MIXED-VALENT TRANSITION METAL OXIDES Mas A. Subramanian, Oregon State University, DMR 1216479 This is an exploratory research project on the identification, synthesis and characterization of new mixed-valent metal oxides with novel functions. The compounds were screened for several properties including multiferroics (dielectric and magnetic properties), superconductivity, magnetoresistance, thermoelectricity, pigments and photocatalysis. Recently, a new class of inorganic color pigments based on Hibonite mineral structure has been discovered. These compounds have a general formula MAl 12 O 19 and crystallize in hexagonal structure (Figure 1). Aluminum cations occupy tetrahedral, octahedral and trigonal bipyramidal coordination making them attractive for exploring color pigments. Ni 2+ substitution for Al 3+ (charge compensated by La 3+ substitution at the Ca site)results in brilliant blue color and results in durable pigments. These pigments show high near infrared reflectivity (high solar heat reflectance) indicating these pigments can be potentially used in 'cool roofing’ applications for ‘greener’ buildings and automobile paints. Many new transition metal oxides with interesting structures and properties were also discovered in this program. For example, we have succeeded in making several new Sn 2+ containing pyrochlores oxides such as Sn 2+ MM’O 6 F (M: Fe, Cr, Mn, Ti, Zr; M’: Nb, Ta, W) and evaluation of their optical, dielectric and photocatalysis properties are in progress. Some of them show bright orange-red colors and may be useful environmentally benign orange-red pigments. Fig. 1. CaAl 12 O 19 structure (hibonite) view evidencing the layered organization of spinel slabs (turquoise and green polyhedra) and trigonal bipyramidal slabs (dark blue). Substitution of Ni2+ (charge compensated by rare earth substitution at the Ca site) produces brilliant blue color and results in durable pigments.

2. Broader impact: A patent application covering the color new blue pigment compositions based on hibonite structure discovered in this program has been filed with US patent office. These pigments have high reflectivity in near IR region (high solar heat reflectance) indicating these pigments can be potentially used in 'cool roofing’ applications for ‘greener’ buildings and automobile paints. This has drawn increased attention from several international pigment/paint manufacturers such as Merck (Darmstadt, Germany) BASF and PPG. Our heat reflecting blue pigment discovery was featured in National Geographic Magazine in 2013 (image shown in the right). Education and Outreach: A demonstration kit showing various color pigments discovered in this program has been developed for outreach actives involving high school students, artists and for general public. Our pigment discovery is widely used in undergraduate projects and outreach activities in many universities. This program is providing training for both undergraduate and graduate students in synthetic materials chemistry, crystal structure analysis and electronic properties The program also train high school students. In 2013-2014, Ms. Bushra Moussaoui, of Philomath High School, Oregon, participated in microwave synthesis of pigments. Students participating in this research program is gaining experience that will prepare them well for the modern academic and industrial environments. Three chemistry undergraduate students and one high school student participated in this program in 2013-14. They are Casey Young (top left, microwave synthesis of pigments), Matthew Stolt (bottom left, photocatalyst synthesis), Omar Rachdi (top right, dielectrics ) and Bushra Moussaoui, Philomath high school, Oregon (microwave synthesis of pigments) MIXED-VALENT TRANSITION METAL OXIDES Mas A. Subramanian, Oregon State University, DMR 1216479 Our Heat Reflecting Pigment discovery highlighted in National Geographic Magazine (2013)