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Rifle-like camera for long distance face recognition

An improved long-range facial recognition system is provided. The facial recognition system includes an integrated, rifle-like mounting platform with modular and interchangeable components, including a machine-vision camera, a facial recognition module, and an aiming scope. The mounting platform includes an elongated frame, a hand grip, a shoulder stock, and an underbody support attachment for an optional bipod. The mounting platform provides an intuitive, shoulder-operated support structure for stabilizing the machine-vision camera and reducing vibrations that otherwise inhibit long distance imaging.

Bolme, David S.↗

Industry Facing PV Degradation Prediction Tool and Database to Enable a 50 Year Life Module

The goal of this work is to create an online tool that can be used to search for degradation information and extrapolate PV module performance and durability to field exposure. A graphical user interface will aid in the understanding of the results. The prediction tool will be built modular and published open-source allowing users to expand on the existing framework.

degradation↗

Industry Facing PV Degradation Prediction Tool and Database to Enable a 50-Year Life Module

The Photovoltaic (PV) industry constantly aims for lower costs, higher-efficiency cells, and improved module designs. These trends lead to using new materials, designs, and manufacturing processes, resulting in a continually changing technological landscape. These changes can potentially introduce new, unknown degradation mechanisms and failure modes that are difficult to diagnose, analyze, test, and model. This introduces uncertainty into the expected lifetime of PV modules of 25 years. Furthermore, research efforts aim for up to 50 years of service life while keeping performance degradation at a minimum for decades of outdoor weathering - putting additional pressure on improving the accuracy of long-term durability and reliability assessments. Here there is a need to organize the existing degradation data into an accessible format and to provide industry relevant tools for extrapolation from laboratory to field conditions. Because the core of this type of analysis involves calculations that are complicated but ubiquitous for many degradation processes, an enhanced predictive modeling framework will facilitate the analysis to help researchers keep up with the rapid pace of technological changes. In this work, we present an online tool that can be used to search for and analyze degradation information and extrapolate PV module performance and durability to field exposure. A graphical user interface will aid in the understanding of the results. The prediction tool will be built modular and published as open source, enabling users to expand on the existing framework. We use an integration pipeline approach that allows us to leverage weather data from the National Solar Radiation Database to perform geospatial degradation analysis in the US and worldwide. Our repository will contain various degradation models and material parameters suitable for the reliability and durability assessment of materials and components deployed outdoors. We hope to become a repository that can be used for weathering and degradation analysis for various applications beyond the PV industry.

degradation↗

U.S. Virgin Islands: Facing Challenges Head-On

The U.S. Virgin Islands (USVI) - located in the Caribbean just east of Puerto Rico between the Caribbean Sea and the north Atlantic Ocean - is composed of three main islands: St. Croix, St. John, and St. Thomas. USVI is confronted with high electricity costs and poor power system reliability, compounded by natural threats like hurricanes, failing infrastructure, and a strained local workforce. Two hurricanes caused widespread damage to power infrastructure in 2017. To combat these challenges, USVI is capitalizing on federal funding opportunities to build a significantly more robust power and water system, paving the way for a brighter and more resilient future.

ENERGY PLANNING, POLICY, AND ECONOMY↗

The New Face of Standard 100

In January 2024, ASHRAE published a significant overhaul to ANSI/ASHRAE/IES Standard 100-2018, Energy Efficiency in Existing Buildings. You may almost not recognize it. Standard 100-2024, Energy and Emissions Building Performance Standard for Existing Buildings, now addresses both energy and emissions performance as a model building performance standard (BPS). ASHRAE Standing Standard Project Committee (SSPC) 100, with direction from ASHRAE and its Task Force for Building Decarbonization (TFBD) has been working to update the standard to make it a model for building performance standard adoption across the U.S. and internationally. Here, the new edition of Standard 100 addresses key issues of climate change surrounding building performance, including new metrics for greenhouse gas (GHG) emissions targets, continuing to support the imperative of improving our existing building stock and meeting global climate change commitments.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Materials Data on Sr20Fe3Co7(MoO6)10 by Materials Project

Sr20Fe3Co7(MoO6)10 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twenty inequivalent Sr sites. In the first Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.10 Å. In the second Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.60–3.08 Å. In the third Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.57–3.08 Å. In the fourth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.07 Å. In the fifth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.62–3.06 Å. In the sixth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.62–3.10 Å. In the seventh Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.57–3.08 Å. In the eighth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.58–3.10 Å. In the ninth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four MoO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.62–3.07 Å. In the tenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.63–3.05 Å. In the eleventh Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.11 Å. In the twelfth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.59–3.09 Å. In the thirteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four MoO6 octahedra, and faces with four CoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.62–3.10 Å. In the fourteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.60–3.05 Å. In the fifteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.08 Å. In the sixteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.13 Å. In the seventeenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.63–3.09 Å. In the eighteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.09 Å. In the nineteenth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, a faceface with one FeO6 octahedra, faces with three CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.61–3.08 Å. In the twentieth Sr site, Sr is bonded to twelve O atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with two FeO6 octahedra, faces with two CoO6 octahedra, and faces with four MoO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.58–3.07 Å. There are ten inequivalent Mo sites. In the first Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–18°. There are a spread of Mo–O bond distances ranging from 1.93–1.98 Å. In the second Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with three FeO6 octahedra, corners with three CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–19°. There are a spread of Mo–O bond distances ranging from 1.92–2.07 Å. In the third Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–19°. There are a spread of Mo–O bond distances ranging from 1.92–1.99 Å. In the fourth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–17°. There are a spread of Mo–O bond distances ranging from 1.93–1.98 Å. In the fifth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–18°. There are a spread of Mo–O bond distances ranging from 1.92–2.00 Å. In the sixth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–17°. There are a spread of Mo–O bond distances ranging from 1.92–1.98 Å. In the seventh Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–17°. There are a spread of Mo–O bond distances ranging from 1.95–2.06 Å. In the eighth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–18°. There are a spread of Mo–O bond distances ranging from 1.92–1.98 Å. In the ninth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–18°. There are a spread of Mo–O bond distances ranging from 1.92–2.00 Å. In the tenth Mo site, Mo is bonded to six O atoms to form MoO6 octahedra that share corners with two FeO6 octahedra, corners with four CoO6 octahedra, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–18°. There are a spread of Mo–O bond distances ranging from 1.94–2.05 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–19°. There are a spread of Fe–O bond distances ranging from 1.96–2.08 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–17°. There are a spread of Fe–O bond distances ranging from 1.97–2.07 Å. In the third Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–17°. There are a spread of Fe–O bond distances ranging from 1.97–2.06 Å. There are seven inequivalent Co sites. In the first Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–17°. There are a spread of Co–O bond distances ranging from 2.02–2.11 Å. In the second Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–18°. There are a spread of Co–O bond distances ranging from 2.07–2.11 Å. In the third Co site, Co is bonded to six O atoms to form CoO6 octahedra that share corners with six MoO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing

36 MATERIALS SCIENCE↗

Materials Data on Ba20Nb19Se60 by Materials Project

Ba20Nb19Se60 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are ten inequivalent Ba sites. In the first Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with five NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 20–25°. There are a spread of Ba–Se bond distances ranging from 3.49–3.68 Å. In the second Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with five NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 16–25°. There are a spread of Ba–Se bond distances ranging from 3.50–3.69 Å. In the third Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with five NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 21–30°. There are a spread of Ba–Se bond distances ranging from 3.53–3.71 Å. In the fourth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 21–22°. There are a spread of Ba–Se bond distances ranging from 3.58–3.62 Å. In the fifth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 15–23°. There are a spread of Ba–Se bond distances ranging from 3.55–3.64 Å. In the sixth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 21–22°. There are a spread of Ba–Se bond distances ranging from 3.55–3.62 Å. In the seventh Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with five NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 21–25°. There are a spread of Ba–Se bond distances ranging from 3.49–3.67 Å. In the eighth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with five NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 20–30°. There are a spread of Ba–Se bond distances ranging from 3.53–3.71 Å. In the ninth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with five NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 20–30°. There are a spread of Ba–Se bond distances ranging from 3.53–3.72 Å. In the tenth Ba site, Ba is bonded to twelve Se atoms to form BaSe12 cuboctahedra that share corners with six BaSe12 cuboctahedra, corners with six NbSe6 octahedra, faces with eight BaSe12 cuboctahedra, and faces with six NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 16–23°. There are a spread of Ba–Se bond distances ranging from 3.55–3.64 Å. There are eleven inequivalent Nb sites. In the first Nb site, Nb is bonded to six Se atoms to form distorted NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and a faceface with one NbSe6 octahedra. There are a spread of Nb–Se bond distances ranging from 2.46–2.83 Å. In the second Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are a spread of Nb–Se bond distances ranging from 2.60–2.68 Å. In the third Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are three shorter (2.63 Å) and three longer (2.65 Å) Nb–Se bond lengths. In the fourth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are five shorter (2.64 Å) and one longer (2.65 Å) Nb–Se bond lengths. In the fifth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are three shorter (2.59 Å) and three longer (2.69 Å) Nb–Se bond lengths. In the sixth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are four shorter (2.64 Å) and two longer (2.65 Å) Nb–Se bond lengths. In the seventh Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are three shorter (2.64 Å) and three longer (2.65 Å) Nb–Se bond lengths. In the eighth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two NbSe6 octahedra. There are five shorter (2.64 Å) and one longer (2.65 Å) Nb–Se bond lengths. In the ninth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two equivalent NbSe6 octahedra. All Nb–Se bond lengths are 2.64 Å. In the tenth Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two equivalent NbSe6 octahedra. All Nb–Se bond lengths are 2.64 Å. In the eleventh Nb site, Nb is bonded to six Se atoms to form NbSe6 octahedra that share corners with six BaSe12 cuboctahedra, faces with six BaSe12 cuboctahedra, and faces with two equivalent NbSe6 octahedra. All Nb–Se bond lengths are 2.64 Å. There are thirty inequivalent Se sites. In the first Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the second Se site, Se is bonded in a distorted single-bond geometry to four Ba and one Nb atom. In the third Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the fourth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 2–67°. In the fifth Se site, Se is bonded in a distorted single-bond geometry to four Ba and one Nb atom. In the sixth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the seventh Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 1–69°. In the eighth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the ninth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the tenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the eleventh Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 1–69°. In the twelfth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 2–68°. In the thirteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the fourteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the fifteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 2–68°. In the sixteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the seventeenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the eighteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the nineteenth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the twentieth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the twenty-first Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 1–68°. In the twenty-second Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 1–69°. In the twenty-third Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the twenty-fourth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–69°. In the twenty-fifth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range from 0–68°. In the twenty-sixth Se site, Se is bonded to four Ba and two Nb atoms to form a mixture of distorted face, edge, and corner-sharing SeBa4Nb2 octahedra. The corner-sharing octahedra tilt angles range f

36 MATERIALS SCIENCE↗