N-芳基-N＇-（4-乙氧基苯甲酰基）硫脲衍生物阴离子识别性能的光谱研究

利用紫外-可见吸收光谱及^1H NMR考察了两种N-芳基-N＇-（4-乙氧基苯甲酰基）硫脲作为受体分子与F^-，Cl^-，Br^-，I^-，CH3COO^-，H2PO4^-，HSO4^-，NO3^-等阴离子的作用。结果表明，客体阴离子F^-，CH3COO^-，H2PO4^-可以与该类受体分子形成氢键配合物，溶液颜色由无色转变为黄色，而加入其他阴离子则无变化。测定了主客体配合物的稳定常数和化学配位比，对苯环上不同取代基的受体分子与不同阴离子客体的识别作用以及同一受体对不同阴离子的识别作用进行了比较，其识别性能呈现规律性变化，提出了可能的配合物的结合模式。     

Effect of various adsorbates in dephasing and population decay of the Cu(1 0 0) image potential states

A theoretical study of the electron dynamics in image potential states on Cu(1 0 0) surfaces with different types of adsorbates is presented. Scattering of the image state electron by an adsorbate induces inter-band and intra-band transitions leading respectively to the population decay and to the dephasing of the image state. We compare results obtained with low coverage (typically 1 adsorbate atom per 1000 surface atoms) Cs, Ar, and a model electronegative adsorbates. As follows from our results, Cs adsorbates lead to both appreciable dephasing and decay, while electronegative adsorbates mostly affect the dephasing rate. The effect of low coverage Ar adsorbates is small, consistent with their neutrality.     

开链冠醚Schiff碱-锌配合物的合成与表征及其PL和EL特性

合成了一种含萘酚基的开链冠醚Schiff碱-锌配合物ZnL（其中配体化合物H2L是N,N’-双（2-羟基-1-萘亚甲基）03,6-二氧杂-1,8-三甘醇二胺）。通过元素分析、红外光谱、差热-热重分析、紫外吸收光谱、荧光光谱和循环伏安法对其结构和性质进行了表征,并成功地制备了基于该材料的电致发光器件。结果表明,ZnL配合物的溶液或固体薄膜在385nm紫外光激发下发光峰为455nm,电致发光器件的最大亮度达到650cd／m^2,在电压为9．5V左右,最大效率达到0．63cd／A。     

时间分辨傅里叶变换红外光谱法研究聚偏氟乙烯的晶变

本文用时间分辨傅里叶变换红外光谱（ＴＲ－ＦＴＩＲＳ）法研究了聚偏氟乙烯（ＰＶＤＦ）的晶型转变，并认５０８ｃｍ＾－１峰的增强和５２８ｃｍ＾－１峰的减弱表示ａ晶型向β晶型的转变，瞬变的初期时间约５ｍｓ，在晶型转变中伴随有“磁滞回线”的非线性效应。     

酞菁铜固态薄膜的红外光谱

利用红外透射光谱，偏振透射光谱、掠角反射光谱研究了三－２，４－二特戊基苯氧基８－喹啉氧基酞菁铜ＬＢ膜和蒸镀膜的结构。确认在ＬＢ膜中，（１）取代基的碳链是以六方晶系或假六方晶系方式堆积的；（２）用偏振红外可以区别苯环上的两个ＣＨ２的伸缩振动带。在蒸镀膜中分子基本呈现无序状态。     

金属羰基化合物[CpFe(CO)_2]_2与金属氧化物表面作用的傅里叶变换漫反射和光声红外光谱研究

用漫反射红外光谱和光声红外光谱法研究了金属羰基化合物［ＣｐＦｅ（ＣＯ）２］２Ｃｐ＝η５—Ｃ５Ｈ５与酸性、中性和碱性Ａｌ２Ｏ３及ＴｉＯ２的相互作用。结果表明，在Ａｌ２Ｏ３表面生成的衍生物种类及浓度与Ａｌ２Ｏ３的酸碱度明显相关。在酸性Ａｌ２Ｏ３表面，主要存在衍生物［ＣｐＦｅ（ＣＯ）２Ｆｅ—Ｈ—Ｆｅ（ＣＯ）２Ｃｐ］＋及少量的ＣｐＦｅ（ＣＯ）２（—Ｏ—）；在中性Ａｌ２Ｏ３表面存在ＣｐＦｅ（ＣＯ）２（—Ｏ—）及较少的［ＣｐＦｅ（ＣＯ）］４；而在碱性Ａｌ２Ｏ３表面主要衍生物为［ＣｐＦｅ（ＣＯ）］４及少量ＣｐＦｅ（ＣＯ）２（—Ｏ—）。衍生物的相对浓度以酸性Ａｌ２Ｏ３表面最高，碱性Ａｌ２Ｏ３表面最低。在ＴｉＯ２表面，［ＣｐＦｅ（ＣＯ）２］２结构基本未变，在空气中比较稳定，没有观察到衍生物的生成。测定了［ＣｐＦｅ（ＣＯ）２］２及其在ＴｉＯ２表面近红外漫反射光谱，指认了大部分观察到的光谱为羰基振动的合频和倍频，并尝试指认了少数光谱为高级（三级）倍频和多元组频（合频）。     

Study of ion desorption induced by a resonant core-level excitation of condensed H2O using Auger electron photo-ion coincidence (AEPICO) spectroscopy combined with synchrotron radiation

Ion desorption induced by a resonant excitation of O 1s of condensed amorphous H₂O has been studied by total ion and total electron yield spectroscopy, nonderivative Auger electron spectroscopy (AES) and Auger electron photo-ion coincidence (AEPICO) spectroscopy. The spectrum of total ion yield divided by total electron yield exhibits a characteristic threshold peak at hν = 533.4 eV, which is assigned to the 4a₁ ← O 1s resonant transition. The AES at the 4a₁ ← O 1s resonance is interpreted as being composed of the spectator-AES of the surface H₂O, and the normal-AES of the bulk H₂O, where the 4a₁ electron is delocalized before Auger transitions. H⁺ is found to be the only ion species in AEPICO spectra measured at the 4a₁ ← O 1s resonance and at the O 1s ionization (hν = 560 eV). The electron kinetic energy dependence of the AEPICO yield (AEPICO yield spectrum) at the 4a₁ ← O 1s resonance is found to be greatly different from that at the O 1s ionization. The peak positions of the AEPICO yield spectrum at the 4a₁ ← O 1s resonance are found to correspond to those of the spectator-AES of the surface H₂O, which is extracted from the AES at the 4a₁ ← O 1s resonance. Furthermore, the AEPICO yield is greatly enhanced at the 4a₁ ← O 1s resonance as compared with that at the O 1s ionization. On the basis of these results, a spectator-Auger-stimulated ion desorption mechanism and/or ultra-fast ion desorption mechanism are concluded to be responsible for the H⁺ desorption at the 4a₁ ← O 1s resonance. The enhancement of the H⁺ yield is ascribed to the O---H anti-bonding character of the 4a₁ orbital.     

Photochemistry in ordered physisorbed monolayers of dinitrogen tetroxide

The effects of physisorption and two-dimensional ordering on the photochemistry of N₂O₄ were investigated. Ordered monolayers were prepared by adsorption of NO₂ at 100 K on a water-ice surface. Irradiation with a continuous light source in the wavelength region 300–400 nm or with pulsed laser radiation at 355 nm resulted in exclusive desorption of NO₂. This desorption was induced by electronic absorption directly in the adsorbate via a transition corresponding to the ( )¹B_2u←( )¹A_g transition in N₂O₄, as in the gas phase. However, the subsequent dynamics in the excited state were markedly different from the gas-phase counterpart. Time-of-flight mass spectrometry of NO₂ photodesorbed at 355 nm revealed a most probable fragment translational energy of ca. 17 meV; and the angular distribution of the nascent NO₂ was peaked sharply in a direction around 10° from the normal. It is apparent that, despite the weak interaction with the substrate, significant energy transfer occurs in the ordered physisorbed monolayer to yield nascent NO₂ with very low translational energy and a constrained angle of escape which is consistent with a high degree of adsorbate order and alignment.     

Quantitative measurements of Ge surface segregation during SiGe alloy growth

Ge segregation during the growth of Si_{1 − x}Ge_x alloys (x = 5, 10, 20, and 40%) was studied using X-ray photoelectron spectroscopy. The alloys were grown in thicknesses up to 20.0 nm at 500°C to measure quantitatively the amount of segregated surface Ge. The length of alloy needed to reach steady-state growth edge was found to decrease with increasing alloy concentration (4.8, 2.8, 2.4, and 2.0 nm, respectively). It was found that each alloy had a complete monolayer of Ge on the surface and an increasing amount of segregated Ge in the second layer (20, 55, 80, and 95%, respectively) during steady-state growth. An increase in the temperature of alloy growth (400–750°C) resulted in an increase in the leading edge of alloy growth but did not change the amount of segregated Ge during steady-state growth. We propose that film stress is responsible for the amount of Ge segregation.     

The adsorption site and orientation of CH3S on Ni(111)

The angle-resolved X-ray photoelectron spectra for 0.15 monolayers (ML) of sulfur, and 0.25 ML methyl thiolate formed at 100 K and annealed to 150 and 250 K, on Ni(111) are analyzed to determine the structures of these species. It is found that sulfur adsorbs on the face-centered cubic hollow site on Ni(111) with a S---Ni bond length of 2.20±0.02 Å. The thiolate species formed at 150 K has the C---S bond tilted at 35° to the surface normal with a C---S bond length of 1.85±0.02 Å and a S---Ni bond length similar to that for adsorbed sulfur (2.2 Å). The methyl group is tilted toward the bridge site and the thiolate appears to be adsorbed on the face-centered cubic site although there may also be adsorption in the hexagonal close packed site. The species formed at 250 K adsorbs on a reconstructed surface where the chemical shift of the S 2p core level indicates that it adsorbs at a four-fold site and the angle-resolved XPS data indicate that the C---S bond is oriented normal to the surface. The calculated angular variations in intensity are consistent with this interpretation but cannot distinguish between the various models proposed for the reconstructed surface.