Simple, selective, and sensitive colorimetric and ratiometric fluorescence/phosphorescence probes for platinum(II) based on Salentype Schiff bases RSC Adv. , 2012 , 2 , 10529 - 10536. L. Zhou, Y. Feng, J. H. Cheng, N. Sun, X. G. Zhou, and H. F. Xiang * Ratiometric fluorescence/phosphorescence probes for Pt 2+ based on the fluorescence quenching from the ligand of Salen-type Schiff bases and phosphorescence enhancement from the resulting Pt(II) complexes have been demonstrated. For phosphorescence enhancement, a good linearity (correlation coefficient R 2 = 0.996, n = 10) was established with detection limit of 11.6 ± 0.2 ppb. The detection limit would be decreased to 2.31 ± 0.03 ppb if degassing was adopted. To the best of our knowledge, this value is one of the most sensitive probes for Pt 2+ . This system also has good selectivity with little interference from Sr 2+ , Sn 2+ , Pb 2+ , Cr 3+ , Mn 2+ , Al 3+ , Fe 3+ , Ce 3+ , Ag + , Li + , Mg 2+ , Na + , Cd 2+ , Cu 2+ , Ca 2+ , Zn 2+ , K + , Co 2+ , Ni 2+ , and Pd 2+ . Moreover, this system is suitable for detection of different Pt(II) sources, such as PtCl 2 , K 2 PtCl 4 , Pt(COD)Cl 2 (COD = 1,5-cyclooctadiene), and cis -platin. It potentially provide a new and simple way to detect some useful transition metal ions, such as Cu + , Au + , Pd 2+ , and Ru 2+ .
http://hyperphysics.phy-astr.gsu.edu/hbase/ligcon.html#c1 散射光是有溶剂,容器表面,胶粒引起的,溶剂和容器引起的是瑞利散射和拉曼散射,瑞利散射峰跟跟激发波长一样,拉曼散射比激发波长稍长,二级瑞利散射和拉曼散射分别在激发波长的二倍和二倍稍长的位置,至于胶粒引起的是丁铎尔散射,它和瑞粒散射一样. 弹性散射（涉及极微小的能量转移）主要有 瑞利散射 和 米氏散射 ( Mie scattering ) 。非弹性散射包括 布里渊散射 ( Brillouin scattering ) 、 拉曼散射 ( Raman scattering ) 、非弹性X-光散射、 康普顿散射 等等。 — 第一类，波数基本不变或变化小于 10 -5 cm -1 ，称为瑞利散射 — 第二类，波数变化大约为 0.1 cm -1 ，称为布里渊散射 — 第三类，波数变化大于 l cm -1 的散射，称为拉曼散射 从散射光的强度看，瑞利散射最强，拉曼散射光最弱 布里渊散射 Relationship to Rayleigh scattering Rayleigh scattering , too, can be considered to be due to fluctuation in the density, composition and orientation of molecules, and hence of refraction index, in small volumes of matter (particularly in gases or liquids). The difference is that Rayleigh scattering considers only random and incoherent thermal fluctuations, in contrast with the correlated, periodic fluctuations (phonons) of Brillouin scattering. Relationship to Raman scattering Raman scattering is another phenomenon involving inelastic scattering processes of light with vibrational properties of matter. The detected frequency shift range and type of information extracted from the sample, however, are very different. Brillouin scattering denominates the scattering of photons from low-frequency phonons , while for Raman scattering photons are scattered by interaction with vibrational and rotational transitions in single molecules. Therefore the two techniques provide very different information about the sample: Raman spectroscopy is used to determine the chemical composition and molecular structure, while Brillouin scattering measures properties on a larger scale – such as the elastic behaviour. Experimentally, the frequency shifts in Brillouin scattering are detected with an interferometer , while Raman setup can be based on either interferometer or dispersive ( grating ) spectrometer . 共振喇曼散射 喇曼散射一般选择远离吸收带的激发波长，在物质的透明区域内进行。当激发光的频率落在分子的吸收带范围内，激发光波长刚好被吸收，这时将产生共振喇曼散射。其强度比喇曼谱线强度约大两至三个数量级，而且光谱的形状也有别于喇曼光谱。这个效应虽然在激光发现之前就已经观察到了，但是采用比汞弧灯的线宽窄得多的激光光源，特别是利用可调频激光来研究共振喇曼散射是特别有效的。利用共振喇曼散射的强度增强效应可以直接测定散射系统样品的微量成分，或者从低浓度的材料获得光谱。加上激光可以被聚焦在微小区域，所以还能对样品成分的分布进行测定。共振喇曼光谱中的强度变化还可以用于环境和结构因素的探测。 丁铎尔散射 tyndall Rayleigh scattering is defined by a mathematical formula that requires the light-scattering particles to be far smaller than the wavelength of the light. For a dispersion of particles to qualify for the Rayleigh formula, the particle sizes need to be below roughly 40 nanometers; and the particles may be individual molecules. Colloidal particles are bigger, and are in the rough vicinity of the size of a wavelength of light. It follows from scattering theory that Tyndall scattering (by colloidal particles) is much more intense than Rayleigh scattering. The importance of the size factor for intensity can be seen in the large exponent it has in the mathematical statement of the intensity of Rayleigh scattering . There is no equivalent mathematical statement for Tyndall scattering. But, if the colloid particles are spheroid , Tyndall scattering is mathematically analysable in terms of Mie theory , which admits particle sizes in the rough vicinity of the wavelength of light. Thomson scattering is the elastic scattering of electromagnetic radiation by a free charged particle, as described by classical electromagnetism . It is just the low-energy limit of Compton scattering : the particle kinetic energy and photon frequency are the same before and after the scattering.
“Synthesis and photophysical properties of water-soluble sulfonato-Salen-type Schiff bases and their applications of fluorescence sensors for Cu 2+ in water and living cells”, Anal. Chim. Acta , 2012 , 735 , 96 - 106. L. Zhou, P. Y. Cai, Y. Feng, J. H. Cheng, H. F. Xiang ,* J. Liu,* D. Wu,* X. G. Zhou ► S ulfonate groups ensure good stability and solubility in water . ► S ulfonate groups have little effect on the photophysical properties. ► This is confirmed by the TD-DFT c alculations and experimental results. ► The strong blue, green, or orange fluorescence is selectively quenched by Cu 2+ . ► T he ligands are sensitive fluorescence sensors for Cu 2+ in water and living cells. A series of water-soluble sulfonato-Salen-type ligands derived from different diamines including 1,2-ethylenediamine ( Et-1 - Et-4 ), 1,2-cyclohexanediamine ( Cy-1 and Cy-2 ) , 1,2-phenylenediamine ( Ph-1 - Ph-3 and PhMe-1 - PhMe-4 ) , and dicyano-1,2-ethenediamine ( CN-1 ) has been designed and prepared. Sulfonate groups of ligands ensure good stability and solubility in water without affecting their excited state properties. Th e se ligands exhibit strong UV/Vis-absorption and blue, green, or orange fluorescence. Time-dependent-density functional theory calculations have been undertaken to reveal the influence of ligand nature, especially sulfonate groups, on the frontier molecular orbitals. Since their fluorescence is selectively quenched by Cu 2+ , the sulfonato-Salen-type ligands can be used as highly selective and sensitive turn-off fluorescence sensors for the detection of Cu 2+ in water and fluorescence imaging in living cells .
“ Tunable fluorescent/phosphorescent platinum(II) porphyrin-fluorene copolymers for ratiometric dual emissive oxygen sensing ”, Inorg. Chem. , 2012 , 51, 5208 - 5212 . H. F. Xiang ,* L. Zhou, Y. Feng, J. H. Cheng, D. Wu, and Xiangge Zhou,* Full text (PDF) A series of new platinum(II) 5,15-bis(pentafluorophenyl)-10,20-bisphenylporphyrin-9,9-dioctyl-fluorene copolymers, in which the relative intensities of the blue fluorescence and red phosphorescence are tunable, have been designed and prepared for the application in ratiometric dual emissive oxygen sensing.
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