黄曲霉素B2分子吸附在银团簇的表面增强拉曼散射机理.pdf

物理化学学报( Wuli Huaxue Xuebao)
Acta Phys.-Chin.Sin.2014,30(10),1916-1922
October
Article
doi;10.3866/PKU.WHXB201407211
ww. whxb. pku.edu. cn
黄曲霉素B2分子吸附在银团簇的表面增强拉曼散射机理
高思敏王红艳林月霞'吴颖曦2胡军1
(西南交通大学峨眉校区基础课部,四川峨眉614202;2西南交通大学物理科学与技术学院,成都610031)
摘要:采用密度泛函理论(DFT)B3LYP方法,6-311(d,p)(C,H,O)ルLANL2DZ(Ag)基组,计算了黄曲霉素B2
(AFB2)分子吸附在Ag2团簇的表面增强拉曼散射(SERS)光譜和预共振拉曼光谱,并与实验结果比较.结果显
示:AFB2分子在基态Ag2团簇表面吸附时,増强因子最大达到103,对应吡喃( pyrane)环C=O伸缩振动,主要是
由AFB2分子周围化学环境改变而引起的基态静柲化率改变导致的化学增强.不同激发波长下的AFB2分子预
共振拉曼光谱的增强强度不同:电荷转移态激发波长为1144和544nm时拉曼信号增强了103倍,而选择电荷
转移预共振波长432和410nm作为入射光时,其拉曼信号增强了10倍,增强机理为银团簇和黄曲霉素分子之
间的电荷转移共振增强.因此通过改变入射光波长,选择电荷转移共振激发波长,吏有利于强致癌物AFB2分子
的浪量检测
关键词:黄曲霉素B2;表面增强拉曼散射光谱;预共振拉曼光谱;密度泛函理论
中图分类号:O641;O647
Surface-enhanced Raman Scattering Mechanism of Aflatoxin B
Molecule Adsorbed on Silver Cluster
GAO Si-min WANG Hon-yan LIN Yue-xia WU Ying-xi HU Jun
(Division offowdat on Courses, E-mei Camus, Southwest aotong Universit, E-mei 614202, Sichuan Province, P R China
School of Physical Science and Technology, Southwest iaotong University, Chengdu 610031, P R. China)
Abstract: The surface-enhanced Raman scattering(SERS)spectrum and pre-resonance Raman spectra
of Aflatoxin B (AFB2 ) adsorbed on silver cluster were calculated by density functional theory(DFT) methods
with the B_YP/6-311G( H, /LANL2DZ(g)basis set. The results show that the SERS enhancement
factors were 10 an this belongs o he C-=O stretching vibration of the pyrane ring because of the larger static
polarizability of the comple. The pre-resonance Raman spectra of the AFB Ag complex were explored at 1144
and 544 nm which corresponds to charge transfer excitation energy, and its enhancement factor was 10. The
pre-resonance enhancement factor was 10 when incident light charge transfer pre-resonant wavelengths of
432 and 4 10 nm were selected. These come from a charge transfer resonance enhancement between the silver
cluster and the AFB molecule. Therefore, changing the wavelength of the incident light is more conducive to
the trace detection of the strong carcinogen AFB2
Key Words: Aflatoxin B2; Surface-enhanced Raman scattering spectrum; Pre-resonant Raman
pectrum; Density functional theo
R
Revised: July 21, 2014; Published on Web: July 21, 2014.
Correspondingauthor.Email:hongyan@home.swjtu.edu.cn;Tel:+86-28-87600963
orted by the National Natural Science Foundat
China (11174237), National Key Basic Rest
(973)
(2013 B328904), Application Basic rogram of Sichuan Province, China(2013J Y0035), and Fundamental Research Funds for the Central
Universities. China
国家自然科学基金(1114237),国家重点基础研究发展计划(973)(2013CB328904),四川省应用基础项目(2013JY0035)及中央高校基本科研业
务费专项资金资助
C Editorial office of Acta Physico-chimica Sinica