BEGIN:VCALENDAR VERSION:2.0 PRODID:Data::ICal 0.22 BEGIN:VEVENT DESCRIPTION:Mina Yoon\, Center for Nanophase Materials Sciences\, Oak Ridge National Laboratory\n\n
Two-dimensional (2D) electrides\, emerging as a new type of layered material whose electrons are confined in interlayer s paces instead of at atomic proximities\, are receiving interest for their high performance in various (opto)electronics and catalytic applications. Experimentally\, however\, 2D electrides have been only found in a couple of layered nitrides and carbides. Here\, we report new thermodynamically s table alkaline-earth based 2D electrides by using a first-principles globa l structure optimization method\, phonon spectrum analysis\, and molecular dynamics simulation. The method was applied to binary compounds consistin g of alkaline-earth elements as cations and group VA\, VIA\, or VIIA nonme tal elements as anions. We revealed that the stability of the layered 2D e lectride structure is closely related to the cation/anion size ratio\; sta ble 2D electrides possess a sufficiently large cation/anion size ratio to minimize electrostatic energy among cations\, anions\, and anionic electro ns. Our work demonstrates a new avenue to the discovery of thermodynamical ly stable 2D electrides beyond the material database and provides new insi ght into the principles of electride design.
\n DTSTART:20161024T150000Z LOCATION:Physics Building\, Room 313 SUMMARY:First-principles predictions of thermodynamically stable two-dimens ional electrides END:VEVENT END:VCALENDAR