Transient Absorption Spectrometer, also called Flash Photolysis Spectrometer is dedicated to measure transitions between quantum states in photo-excited sample. TA measurements are applicable to liquid and solid sample types.
The sample in the ground state is energized to an excited state with an intense laser pulse. The pulse may induce short lived intermediates such as electrons at higher energy levels, radicals or ions.
Process of deexcitation is monitored by measurement of the Transmittance/Absorbance of the white light beam going through the sample in case of a liquids and thin films or Reflectance of the sample in case of powders and non transparent bulk samples. The white light beam is produced by the Xenon Lamp.

System provides functionality that enables measurements of fluorescence and phosphorescence induced with the laser pulse.

With the Electrochemical extension, solid state samples submerged in electrolyte  can be investigated. When sample in contact with an electrolyte is examined, additional bias potential may be applied during the experiment. That gives one more control parameter and extends flexibility of the experiment.

If also the Analog Potentiostat is used, one can follow changes in current flowing between a sample and the electrolyte on the time scales of a single laser pulse!

Experimental procedures are fully automated.

Quantities measured by the instrument:

• Transmittance/Absorbance or Reflectance of the sample in nanosecond time scale,
• Laser-induced fluorescence spectrum,
• Life time of the photo-excited transients,
• Laser beam intensity on the input and the output of the sample chamber,
• I-V characteristics of the electrochemical samples (with Electrochemical extension).
• Electric current between the sample and electrolyte during laser pulse (with Analog Potentiostat)

1. Closed sample chamber.
2. Xenon Lamp with water cooling system and the Pulser.
3. Laser, typically Nd:YAG with possibility of choosing higher harmonics or even OPO.
4. Monochromator for UV, VIS and IR spectrum range.
5. Osciloscope.
6. Photomultiplier.
7. Timer synchronizing all the components of the system.
8. Potentiostat providing full characteristics of the electro-chemical sample.
9. Electro-chemical cuvette with platinum electrode and Ag/AgCl reference.

Sample chamber

Sample chamber screens the measurement setup from background diffused light and external electromagnetic fields.  It is equipped with a safety system that disconnects power supply of the Xenon Lamp and laser source after opening the chamber and system of easy and stable installation of several different experimental setups.

Inner measurement setups with different optical paths and sample cuvettes may be provided and adjusted to the individual experimental requirements.

Transient Absorption.

Laser-Induced Fluorescence.

Sample Chamber

• Safety system that disconnects the power supply of the Xenon Lamp and the Laser when the Sample Chamber is opened,
• Easy and stable installation of several different experimental setups with sample cuvettes,
• Two photodiodes: at the chamber entrance and output to measure laser pulse power,

Xenon Lamp

• 150 W xenon burner,
• Water cooling system,
• Low EM emission igniter,
• Light intensity stabilization mode that provides constant light power of the beam,
• Default beam diameter: 8 mm,
• Coupled with a Filter Wheel to modify the probing spectrum,

Xenon Lamp Pulser

• Pulse duration: 2 µs ÷ 2 ms,
• Pulse current: 8.5 ÷ 595 A.

Laser source

Quantel Q-Smart

• Laser type: Nd:YAG with 1064 nm base line,
• Up to four Harmonic Generation Modules: 213 nm, 266 nm, 355 nm, 532 nm,
• Beam diameter: 5 mm,
• Pulse duration: 5 ns,
• Beam power: 532 nm: 200 mJ, 350 nm: 100 mJ (10 Hz),

Any other laser type or OPO may be used at the sample chamber entrance.

Filter Wheels

• Up to 6 filters,
• Two edge (long pass) filters provided by default: 400 nm and 600 nm,
• Optional Air Mass Filter installed in the Filter Wheel coupled with the Xenon Lamp,

Photomultiplier

R928P Hammamatsu

• Anode to Cathode voltage range: 500 ÷ 1200 V,
• Spectral range: 160 ÷ 900 nm,

瞬态吸收光谱仪，也称为闪光光解光谱仪，专门用于测量光激发样品中量子态之间的跃迁。TAS 测量适用于液体和固体样品。
样品在基态下通过强激光脉冲激发到激发态。该脉冲可能引发短寿命的中间体，如处于较高能级的电子、自由基或离子。
去激发过程通过测量透过样品的白光束的透过率/吸光度来监测，在液体和薄膜的情况下，或者在粉末和不透明的块体样品的情况下，测量样品的反射率。白光束由氙灯产生。

系统提供的功能使得可以测量激光脉冲引发的荧光和磷光。

通过电化学扩展，可以研究浸入电解质中的固态样品。当样品与电解质接触时，可以在实验过程中施加附加的偏置电压。这提供了一个额外的控制参数，并扩展了实验的灵活性。

如果还使用模拟电位仪，则可以在单个激光脉冲的时间尺度上跟踪样品与电解质之间流动的电流变化！

实验过程完全自动化。

仪器测量的量：

• 样品在纳秒时间尺度上的透过率/吸光度或反射率，
• 激光引发的荧光光谱，
• 光激发瞬态的寿命，
• 激光束在样品室输入和输出处的强度，
• 电化学样品的I-V特性（带电化学扩展），
• 激光脉冲期间样品与电解质之间的电流（带模拟电位仪）。

1. 封闭样品室。
2. 氙灯，配有水冷系统和脉冲器。
3. 激光器，通常为Nd:YAG，并可以选择更高的谐波或甚至OPO。
4. 单色仪，适用于紫外、可见光和红外光谱范围。
5. 示波器。
6. 光电倍增管。
7. 定时器，用于同步系统的所有组件。
8. 电位仪，用于提供电化学样品的完整特性。
9. 配有铂电极和Ag/AgCl参考电极的电化学比色皿。

样品室

样品室能够将测量设备与背景散射光和外部电磁场隔离开来。它配备了一个安全系统，在打开样品室后能够切断氙灯和激光源的电源，并且具有方便且稳定的多个不同实验装置安装系统。

内部的测量装置配有不同的光路和样品比色皿，可以根据个别实验需求进行提供和调节。

瞬态吸收

激光引发的荧光

样品室

• 安全系统，在样品室打开时切断氙灯和激光器的电源，
• 便捷且稳定的多个不同实验装置及样品比色皿的安装，
• 两个光电二极管：分别位于样品室入口和出口，用于测量激光脉冲功率，

氙灯

• 150 W 氙灯灯泡，
• 水冷系统，
• 低电磁辐射点火器，
• 光强稳定模式，提供恒定的光束功率，
• 默认光束直径：8 毫米，
• 与滤光轮配合使用，以修改探测光谱，

氙灯脉冲器

• 脉冲持续时间：2 µs ÷ 2 ms，
• 脉冲电流：8.5 ÷ 595 A。

激光源

Quantel Q-Smart

• 激光类型：Nd:YAG，基线波长为1064 nm，
• 最多可配备四个谐波生成模块：213 nm、266 nm、355 nm、532 nm，
• 光束直径：5 毫米，
• 脉冲持续时间：5 ns，
• 光束功率：532 nm：200 mJ，350 nm：100 mJ（10 Hz），

任何其他类型的激光或OPO都可以在样品室入口处使用。

滤光轮

• 最多可安装6个滤光片，
• 默认提供两个边缘（长通）滤光片：400 nm和600 nm，
• 可选的空气质量滤光片安装在与氙灯配合使用的滤光轮中，

光电倍增管

R928P Hammamatsu

• 阳极到阴极的电压范围：500 ÷ 1200 V，
• 光谱范围：160 ÷ 900 nm，