Time-dependent fifth-order bands in nominally third-order 2D IR vibrational echo spectra.
Time-dependent fifth-order bands in nominally third-order 2D IR vibrational echo spectra.
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名义上三阶二维红外振动回波光谱中与时间相关的五阶频带。
DOI：
10.1021/jp201516s
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Fayer,MichaelD
中科院分区：
文献类型：
--
作者：
Thielges,MeganC;Fayer,MichaelD
2D IR振动光谱学领域的进展得到了强中红外激光脉冲产生的支持。随着采用更高能量的脉冲，伴随的增加发生在第五阶贡献的2D IR光谱的可能性。我们报告的外观五阶信号的二维红外光谱中的CO结合到酶细胞色素P450 CAM与底物去甲樟脑的活性位点。两个带与新的时间依赖性，一个在对角线上，一个非对角线，不占正常的三阶相互作用。这些带与av= 1-2振动跃迁频率有关。两个带衰减到0，然后以相反的符号重新生长。对角线带在短时间内为正，衰减到0，在最终衰减到0之前以负号重新出现。非对角带在短时间内为负，衰减到0，重新出现为正，然后衰减到0。这些频带的外观和时间依赖性的特点。理解这些五阶能带是有用的，因为它们可能会与其他过程（如化学交换，振动耦合或能量转移）产生的时间相关能带相混淆。的存在和不寻常的时间依赖性的第五阶带再现与模型计算，占的事实，即振动弛豫从thev= 2到1的水平是大约一个因子2快于从thev= 1到0的水平。
Progress in the field of 2D IR vibrational spectroscopy has been bolstered by the production of intense mid-IR laser pulses. As higher-energy pulses are employed, a concomitant increase occurs in the likelihood of fifth-order contributions to the 2D IR spectra. We report the appearance of fifth-order signals in 2D IR spectra of CO bound to the active site of the enzyme cytochrome P450camwith the substrate norcamphor. Two bands with novel time dependences, one on the diagonal and one off-diagonal, are not accounted for by normal third-order interactions. These bands are associated with av= 1–2 vibrational transition frequency. Both bands decay to 0 and then grow back in with opposite sign. The diagonal band is positive at short time, decays to 0, reappears with negative sign, before eventually decaying to 0. The off-diagonal band is negative at short time, decays to 0, reappears positive, and then decays to 0. The appearance and time dependence of these bands are characterized. Understanding these fifth-order bands is useful because they may be misidentified with time-dependent bands that arise from other processes, such as chemical exchange, vibrational coupling, or energy transfer. The presence and unusual time dependences of the fifth-order bands are reproduced with model calculations that account for the fact that vibrational relaxation from thev= 2 to 1 level is approximately a factor of 2 faster than that from thev= 1 to 0 level.
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DOI：
10.1021/jp911452z
发表时间：
2010-02-25
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Rosenfeld DE;Kwak K;Gengeliczki Z;Fayer MD
通讯作者：
Fayer MD
恶臭假单胞菌细胞色素P-450cam基因的核苷酸序列及其在大肠杆菌中的表达。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Unger,BP;Gunsalus,IC;Sligar,SG
通讯作者：
Sligar,SG
底物类似物诱导细胞色素 P450cam-一氧化碳复合物中 CO 拉伸模式的变化。
影响因子：
2.9
作者：
C. Jung;G. H. Hoa;K. Schröder;M. Simon;J. Doucet
通讯作者：
J. Doucet
血红素环境极性对细胞色素 P-450cam-CO 中 CO 拉伸模式的作用。
影响因子：
2.9
作者：
C. Jung;H. Schulze;E. Deprez
通讯作者：
E. Deprez
影响因子：
15
作者：
Thielges MC;Chung JK;Fayer MD
通讯作者：
Fayer MD