346 0

Weak antiferromagnetic superexchange interaction in fcc C60Hn

Title
Weak antiferromagnetic superexchange interaction in fcc C60Hn
Author
조준형
Keywords
MAGNETIC-PROPERTIES; SPIN POLARIZATION; FULLERENES; FULLERIDES; CARBON; MODEL; C-60
Issue Date
2012-08
Publisher
AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Citation
Physical Review B, Vol. 86, No. 8 (2012)
Abstract
A recent density-functional calculation for fcc C60Hn (n = odd) [ K.W. Lee and C. E. Lee, Phys. Rev. Lett. 106, 166402 (2011)] proposed the existence of Stoner ferromagnetism based on an itinerant band model. However, our density-functional calculation shows that the antiferromagnetic (AFM) configuration is slightly more stable than the ferromagnetic (FM) one. This preference for antiferromagnetism over ferromagnetism is analogous to the case of a dimer (C60H)(2), where each C60H is spin polarized by an intramolecular exchange and the two magnetic moments are antiferromagnetically coupled with each other. The results demonstrate that the underlying mechanism of the magnetic order in fcc C60Hn is associated with the AFM superexchange between the magnetic moments created by H dopants.최근의 제일원리 밀도 범함수 이론계산 연구[K. W. Lee and C. E. Lee Phys. Rev. Lett. 106 166402 (2011)]는 FCC 결정구조를 가지는 C60 결정에 수소가 홀 수개 흡착하였을 때 itinerant band model에 의해 stoner ferromagnetism이 존재함을 제안하였다. 하지만, 우리의 범함수 이론계산은 FCC C60Hn(n=홀수)에서 반자성 상태가 강자성 상태보다 약간 더 안정됨을 보인다. 강자성 상태보다 반강자성 상태가 더 안정되는 이러한 경향성은 dimer (C60H)2 분자에서도 유사한데, 각 C60H가 intramolecular exchange에 의해 스핀 분극화되고 각 C60H의 두개의 자기모멘트는 반강자성으로 정렬된다. 이러한 결과는 FCC C60Hn(n=홀수)에서 반강자성 현상의 메커니즘이 H dopants에 의해 생긴 자기 모멘트들 사이의 반강자성 superexchange interaction과 연관됨을 증명한다.
URI
http://journals.aps.org/prb/abstract/10.1103/PhysRevB.86.081415http://hdl.handle.net/20.500.11754/40995
ISSN
1098-0121
DOI
10.1103/PhysRevB.86.081415
Appears in Collections:
COLLEGE OF NATURAL SCIENCES[S](자연과학대학) > PHYSICS(물리학과) > Articles
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE