Simple evaluation of Franck–Condon factors and non‐Condon effects in the Morse potential

The calculation of Franck–Condon factors between different 1‐D Morse potential eigenstates using a formula derived from the Wigner function is discussed. Our numerical calculations using a simple program written in Mathematica are compared with other calculations. We show that our results have a similar accuracy as those calculations performed with more sophisticated methods. We discuss the extension of our method to include non‐Condon effects in the calculation. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem 88: 280–295, 2002     

钙钛矿型CaSiO_3解压缩和重压缩过程的分子动力学模拟

用分子动力学模拟方法 (MD)研究了 3 0 0K时钙钛矿型CaSiO3 ,从高压到负压的解压缩过程 .MD模拟获得的P V关系与实验数据相近 ,与已报道的MD模拟数据基本一致 ,所得体积模量也在实验数据分布范围内 .减压缩和重压缩的MD模拟数据与实验结果相似 .钙钛矿型CaSiO3 解压缩成非晶态时 ,存在两个结构破坏阶段 :破坏硅氧八面体和破坏钙氧二十面体 .当钙氧二十面体被破坏后 ,重压缩不能得到钙钛矿型结构 .只要钙氧二十面体未被破坏 ,重压缩可恢复钙钛矿型结构 .本研究得到的结果尚未见相关报道 .由MD模拟数据计算了CaSiO3 系统的红外光谱 ,分析这些数据可知钙钛矿型CaSiO3 解压缩非晶化是一个二阶软模相变 .研究表明钙钛矿型CaSiO3 结构存在一个等容的亚稳极限 ,其解压缩非晶化是一个受动力学控制的亚稳状态 .     

Nanoporous TiO2 Coatings for Infrared Detectors

In GaAs based infrared detectors, a considerable part of the incident light will be reflected at the surface, thus it decreases the detectors sensitivity considerably. In this paper, a TiO₂ nanoporous coating was prepared successfully on the GaAs substrate by sol-gel method. The optical parameters of the coating were also controlled successfully. It was proved that the coating could greatly improve the transmittance of the incident light, which agrees with the theoretical results quite well. In the 2.5–6.0 m waveband, the maximum transmittance of GaAs substrate is 56%, while the transmittance of the GaAs substrate coated with a nanostructured TiO₂ coating is about 94%.     

完全未知混合体系中纯组份的红外光谱解析

提出一种新的目标转化因子分析，其初始向量的构造基于实际最大差异光谱，无需分离即可从红外混合体系中解析出纯组份光谱。该算法简单易懂，不必迭代，运算量小，应用于模拟及实际体系，结果令人满意。     

磁疗手术胆结石的红外光谱观测

本文报道用Nicolet 170 SXFT-IR红外光谱仪观测磁疗手术胆结石、磁疗破碎排出胆结石及服中草药破碎胆结石的红外光谱,分析并比较了它们的光谱特征。     

FOURIER TRANSFORM FAR INFRARED SPECTRA AND NORMAL COORDINATE ANALYSIS OF FIFTEEN RARE-EARTH OXALATE HYDRATES

The Fourier transform far infrared spectra of oxalate hydrates of whole rare-earth series except Pm and Sc are investigated in the range of 100-400 cm~(-1). The assignment of vibrational frequencies is made on the basis of normal coordinate analysis using our NORVIB program. The model used for the hghter elements of the lanthanide series (La to Eu) is based on the crystal structure of Nd_2(C_2O_4)_3. 10H_2O, in which each lanthanide ion is surrounded by nine O atoms, six from three oxalate ions and three from Water molecules.The model adopted for the heavier elements of the lanthanide series (Gd to Lu) and Ytterbium is based on the crystal structure of Yb_2(C_2O_4)_3· 6H_2O, in which each ion is surrounded by eight atoms, six from three oxalate ions and two from water molecules. The variation of the metal-ligand frequencies and force constants with the atomic numbers of lanthanides is plotted and discussed.     

重整汽油近红外光谱的稳健偏最小二乘解析

近红外光谱(ＮＩＲ)光谱复杂,组分间光谱重叠严重,目前,多元线性回归(ＭｕｌｔｉｐｌｅＬｉｎｅａｒＲｅ ｇｒｅｓｓｉｏｎ,ＭＬＲ)和偏最小二乘法(ＰａｒｔｉａｌＬｅａｓｔ ｓｑｕａｒｅｓ,ＰＬＳ)是近红外光谱分析中使用最多和效果较好的方法[1]。稳健偏最小二乘(ＲｏｂｕｓｔＰａｒｔｉａｌＬｅａｓｔ Ｓｑｕａｒｅｓ,ＲＰＬＳ)是由稳健统计学构造的具有稳健性能的多元校正方法。当化学测量中引入随机异常点或误差的内在分布偏离正态分布时,它仍能给予接近最优性能的校正,确保分析结果的准确性,是消除奇异点的非常有效的方法[2-4],…     

丹皮酚的电化学氧化及其反应机理研究

研究了在碱性磷酸盐缓冲溶液体系中,丹皮酚在固体电极上的电化学吸附氧化行为。与苯酚的电化学性质比较表明,碱性溶液中丹皮酚在电极表面上发生类似的不可逆的氧化。氧化产物发生随后化学反应,在电极表面生成致密的不导电聚合物膜。利用超微电极技术研究了丹皮酚电化学氧化的动力学过程,并用时间分辨快速扫描现场红外光谱电化学证明了电极表面的聚合物膜是芳醚类聚合物。     

Applications of chalcogenide glass optical fibers

Chalcogenide-glass fibers based on sulfide, selenide, telluride and their rare-earth-doped compositions are being actively pursued worldwide. Great strides have been made in reducing optical losses using improved chemical purification techniques, but further improvements are needed in both purification and fiberization technology to attain the theoretical optical losses. Despite this, chalcogenide-glass fibers are enabling numerous applications that include laser power delivery, chemical sensing, and imaging, scanning near field microscopy/spectroscopy, IR sources/lasers, amplifiers and optical switches.