Upgrade of ESR Facility

哥伦比亚大学化学系将用这笔奖金购买两台电子自旋共振（ESR）光谱仪的升级版。这两种仪器都能够在稳态运行和时间分辨ESR实验中获得ESR光谱。傅里叶变换（FT） ESR方法也将实现。这两种仪器都将配备能够提供纳秒脉冲的激光器，用于激发样品和产生顺磁瞬变。该部门的成员将使用这些仪器进行广泛的工作，并将用于各种最先进的实验，包括：1)采用时间分辨激光闪光光解气相实验，探讨利用圆偏振光产生反应产物电子自旋极化的可能性；​2)研究新材料磁性的低温实验；3)室温溶液实验，采用时间分辨方法研究有机三重态和自由基的电子极化转移，以阐明顺磁性物质之间的电子交换机制；4)低温电子自旋回波包络调制（ESEEM）实验研究光合反应中心。电子自旋共振（ESR）光谱仪是一种用于获取分子和分子电子结构信息的仪器。它也可用于获得自由基寿命的信息，自由基对于肿瘤生长和/或各种化学反应的开始通常是必不可少的。

The Department of Chemistry at Columbia University will use this award for the purchase of an upgrade for two electron spin resonance (ESR) spectrometers. Both instruments are capable of acquiring ESR spectra in steady state operation and in time-resolved ESR experiments. Fourier transform (FT) ESR methods will also be implemented. Both instruments will be equipped with lasers capable of providing nanosecond pulses for excitation of samples and the production of paramagnetic transients. The instruments will be used by members of the department for a wide range of work and will be used for a variety of state-of-the-art experiments including: 1) Gas phase experiments employing time resolved laser flash photolysis to investigate the possibility of employing circularly polarized light to produce electron spin polarization of reaction products; 2) Low temperature experiments which investigate the magnetic characteristics of novel materials; 3) Room temperature solution experiments which employ time resolved methods to investigate electron polarization transfer for organic triplet states and radicals in order to elucidate the mechanism of electron exchange between paramagnetic species; and 4) Low temperature electron spin echo envelope modulation (ESEEM) experiments to investigate photosynthetic reaction centers. %%% An electron spin resonance (ESR) spectrometer is an instrument used to obtain information about the molecular and electronic structure of molecules. It may also be used to obtain information about the lifetimes of free radicals which are often essential for the initiation of tumor growth and/or a variety of chemical reactions.