We use first-principles density functional theory within the local density approximation to ascertain the ground state structure of real and theoretical compounds with the formula ABS3 (A = K, Rb, Cs, Ca, Sr, Ba, Tl, Sn, Pb, and Bi; and B = Sc, Y, Ti, Zr, V, and Nb) under the constraint that B must have a d(0) electronic configuration. Our findings indicate that none of these AB combinations prefer a perovskite ground state with corner-sharing BS6 octahedra, but that they prefer phases with either edge- or face-sharing motifs. Further, a simple two-dimensional structure field map created from A and B ionic radii provides a neat demarcation between combinations preferring face-sharing versus edge-sharing phases for most of these combinations. We then show that by modifying the common Goldschmidt tolerance factor with a multiplicative term based on the electronegativity difference between A and S, the demarcation between predicted edge-sharing and face-sharing ground state phases is enhanced. We also demonstrate that, by calculating the free energy contribution of phonons, some of these compounds may assume multiple phases as synthesis temperatures are altered, or as ambient temperatures rise or fall.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1063/1.4879659 | DOI Listing |
J Clin Ultrasound
January 2025
JD Hamilton Consulting, Brighton, Michigan, USA.
Background: Ultrasound lung surface motion measurement is valuable for the evaluation of a variety of diseases. Speckle tracking or Doppler-based techniques are limited by the loss of visualization as a tracked point moves under ribs or is dependent.
Methods: We developed a synthetic lateral phase-based algorithm for tracking lung motion to overcome these limitations.
BMC Plant Biol
January 2025
State Key Laboratory of Tree Genetics and Breeding, Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, 650233, PR China.
The slope aspect is an important environmental factor, which can indirectly change the acceptable solar radiation of forests. However, the mechanism of how this aspect changes the underground ecosystem and thus affects the growth of aboveground trees is not clear. In this study, Pinus yunnanensis plantation was taken as the research object, and the effects of soil and microbial characteristics on tree growth under different slope aspects and soil depths were systematically analyzed.
View Article and Find Full Text PDFLife Sci Space Res (Amst)
February 2025
Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.
Future long duration space missions will expose astronauts to higher doses of galactic cosmic radiation (GCR) than those experienced on the international space station. Recent studies have demonstrated astronauts may be at risk for cardiovascular complications due to increased radiation exposure and fluid shift from microgravity. However, there is a lack of direct evidence on how the cardiovascular system is affected by GCR and microgravity since no astronauts have been exposed to exploratory mission relevant GCR doses.
View Article and Find Full Text PDFJMIR Ment Health
January 2025
The Samueli Initiative for Responsible AI in Medicine, Tel Aviv University, Tel Aviv, Israel.
Generative artificial intelligence (GenAI) shows potential for personalized care, psychoeducation, and even crisis prediction in mental health, yet responsible use requires ethical consideration and deliberation and perhaps even governance. This is the first published theme issue focused on responsible GenAI in mental health. It brings together evidence and insights on GenAI's capabilities, such as emotion recognition, therapy-session summarization, and risk assessment, while highlighting the sensitive nature of mental health data and the need for rigorous validation.
View Article and Find Full Text PDFWater Res
January 2025
State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
Cyanobacterial blooms are increasingly becoming major threats to global inland aquatic ecosystems. Phycocyanin (PC), a pigment unique to cyanobacteria, can provide important reference for the study of cyanobacterial blooms warning. New satellite technology and cloud computing platforms have greatly improved research on PC, with the average number of studies examining it having increased from 5 per year before 2018 to 17 per year thereafter.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!