Spectroscopy Of NO Research Articles

High-resolution laser magnetic resonance and infrared-radiofrequency double-resonance spectroscopy of NO and its isotopes near 5.4 μm

The fundamental band of NO has been investigated by the laser magnetic resonance method, in which the absorption lines from an NO sample located inside the laser cavity were Zeeman tuned into resonance with fixed CO laser transitions. Saturation dips with a width of <2 MHz were observed, allowing the resolution of hyperfine and Λ-doubling structure in the NO spectrum. Transitions due to the weak 2-1 “hot” band and the 2 Π 1 2 ← 2 Π 1 2 satellite band of 14N 16O were observed, as were transitions due to the 15N 16O, 14N 18O, and 14N 17O isotopic species in natural abundance. Data from the present work were combined with previous measurements to obtain a consistent set of vibration-rotation parameters for five isotopic species of NO. An infrared-radiofrequency double-resonance spectrum was observed which allowed the precise (∼20 kHz) measurement of some hyperfine Λ-doubling transitions within the v = 1 state of 14N 16O.

Zeeman spectroscopy of NO with the magnetospectrophone

Immersion of a spectrophone in a magnetic field gives an instrument (the magnetospectrophone or MSP) that can in combination with a laser source be used to detect and study gases showing a Zeeman effect. Experiments are described using a fixed tuned CO laser source with the MSP to observe the Zeeman spectrum of NO. Possible other uses include detection of free radicals and monitoring of stratospheric chemistry. The electric analog (the electrospectrophone or ESP) could be used to study the Stark effect.

Microwave optical double resonance and continuous wave dye laser excitation spectroscopy of NO 2: Rotational assignment of the K = 0−4 subbands of the 593 nm band

A rotational assignment of approximately 80 lines with K a ′ = 0, 1, 2, 3, and 4 has been made of the 593 nm 2A 1 → 2B 2 band of NO 2 using cw dye laser excitation and microwave optical double-resonance spectroscopy. Rotational constants for the 2 B 2 state were obtained as A = 8.52 cm −1, B = 0.458 cm −1, and C = 0.388 cm −1. Spin splittings for the K a ′ = 0 excited state levels fit a simple symmetric top formula and give (ϵ bb + ϵ cc) 2 = −0.0483 cm −1 . Spin splittings for K a ′ = 1 ( N′ even) are irregular and are shown to change sign between N′ = 6 and 8. Assuming that the large inertial defect of 4.66 amu Å 2 arises solely from A, a structure for the 2 B 2 state is obtained which gives r (NO) = 1.35 A ̊ and an ONO angle of 105°. Alternatively, weighting the three rotational constants equally gives r = 1.29 A ̊ and θ = 118°.

NO spectroscopy at 100 °K with a PbS0.4Se0.6 diode laser

NO spectroscopy at temperatures up to 100 °K was achieved with a pulsed PbS0.4Se0.6 diode laser. A frequency chirping rate of about 0.3 cm−1/μs was obtained. The variation of the threshold current density and laser wavelength versus temperature is presented.