A vacuum ultraviolet flash photolysis apparatus

Area of Science:

• Chemical Physics
• Spectroscopy
• Photochemistry

Background:

• Kinetic spectroscopy is crucial for understanding chemical reaction dynamics.
• Vacuum ultraviolet (VUV) photolysis offers unique excitation pathways.
• Existing VUV flash photolysis setups may have limitations in performance or design.

Purpose of the Study:

• To construct and describe an improved apparatus for vacuum ultraviolet (VUV) flash photolysis-kinetic spectroscopy.
• To enhance the precision and efficiency of VUV photolysis experiments.
• To facilitate detailed kinetic studies of chemical reactions initiated by VUV light.

Main Methods:

• A compact, coaxial design featuring six capacitors and electrode pairs around a hexagonal reaction vessel.
• Use of lithium fluoride (LiF) windows for efficient transmission of far ultraviolet radiation.
• Synchronous firing of electrodes and capacitors for uniform illumination of the reaction cell.

Main Results:

• The apparatus delivers a photolytic light pulse of approximately 5 microseconds duration.
• More than 10^18 quanta are introduced into the reaction vessel in the 1050-1600 A spectral range.
• The construction allows for uniform and efficient photolysis within the reaction cell.

Conclusions:

• The developed apparatus represents a significant improvement for VUV flash photolysis-kinetic spectroscopy.
• The design facilitates high-intensity, short-duration photolysis for kinetic studies.
• The essential operating features enable detailed investigation of photochemical processes.