Dilute magnetic III–V semiconductor spintronics materials: A first-principles approach
摘要:
Group-III nitride semiconductors, such as GaN, when doped with 3d transition metals such as Mn or Cr show ferromagnetism with high Curie temperature. Such dilute magnetic semiconductors (DMS) with larger band gaps and smaller lattice constants compared to GaAs based DMS, are potential candidates for room temperature spintronics devices. We have investigated the magnetic coupling between doped Mn (or Cr) atoms in clusters as well as crystals of GaN from first principles using molecular orbital theory for (GaN)(x)TM2 clusters and TB-LMTO band calculations for wurtzite structured (Ga14TM2)N-16 supercells. Our calculations reveal that the coupling between TM-impurity atoms is ferromagnetic with a bulk magnetic moment of similar to 3.5 mu(B) per Mn atom and similar to 2.7 mu(B) per Cr atom. (c) 2005 Elsevier B.V. All rights reserved.
A Study on the Friedel-Crafts Type Reaction of Ninhydrin with Arenes
作者:Hyun Nam Song、Mi Ra Seong、Ji Suk Son、Jae Nyoung Kim
DOI:10.1080/00397919808007017
日期:1998.5
Abstract The reactions of ninhydrin (1, 1,2,3-indantrione) with arenes in the presence of concentrated sulfuric acid afforded mono- or di-substituted ninhydrin derivatives at the 2-position in reasonable yields.
Dilute magnetic III–V semiconductor spintronics materials: A first-principles approach
作者:G.P. Das、B.K. Rao、P. Jena、Y. Kawazoe
DOI:10.1016/j.commatsci.2005.07.004
日期:2006.5
Group-III nitride semiconductors, such as GaN, when doped with 3d transition metals such as Mn or Cr show ferromagnetism with high Curie temperature. Such dilute magnetic semiconductors (DMS) with larger band gaps and smaller lattice constants compared to GaAs based DMS, are potential candidates for room temperature spintronics devices. We have investigated the magnetic coupling between doped Mn (or Cr) atoms in clusters as well as crystals of GaN from first principles using molecular orbital theory for (GaN)(x)TM2 clusters and TB-LMTO band calculations for wurtzite structured (Ga14TM2)N-16 supercells. Our calculations reveal that the coupling between TM-impurity atoms is ferromagnetic with a bulk magnetic moment of similar to 3.5 mu(B) per Mn atom and similar to 2.7 mu(B) per Cr atom. (c) 2005 Elsevier B.V. All rights reserved.
Acid-Catalyzed Condensations of Ninhydrin with Aromatic Compounds. Preparation of 2,2-Diaryl-1,3-indanediones and 3-(Diarylmethylene)isobenzofuranones<sup>1</sup>
作者:Douglas A. Klumpp、Shyla Fredrick、Siufu Lau、Kevin K. Jin、Robert Bau、G. K. Surya Prakash、George A. Olah
DOI:10.1021/jo990197h
日期:1999.7.1
Ninhydrin (1) reacts with aromaticcompounds in acid solution to give condensation products. In H2SO4, 1 reacts with arenes to give 2,2-diaryl-1,3-indanediones (2a-f). In superacidic triflic acid (CF3SO3H, TfOH), 1 reacts with arenes to give 3-(diarylmethylene)isobenzofuranones (3a-e). Products 3a-e are proposed to have formed by a condensation and rearrangement involving dicationic intermediates.