Vol. 35, issue 05, article # 3

Bobrovnikov S. M., Gorlov E. V., Zharkov V. I., Murashko S. N. Estimation of the efficiency of laser excitation of the B2Σ+ (v´ = 0) - X2Π (v´´ = 0) transition of phosphorus oxide. // Optika Atmosfery i Okeana. 2022. V. 35. No. 05. P. 361–368. DOI: 10.15372/AOO20220503 [in Russian].
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We present the results of calculating the vibrational and rotational terms of the X2Π and B2Σ+ electronic states of the phosphorus oxide (PO) molecule. The absorption spectrum corresponding to the electronic transition B2Σ+ (v´ = 0) - X2Π (v´´ = 0) has been calculated. The efficiency of laser excitation of PO molecules is estimated as a function of the spectral parameters of the radiation. It has been established that the excitation efficiency of the B2Σ+ (v´ = 0) - X2Π (v´´ = 0) electronic transition of the PO molecule is approximately an order of magnitude lower than that of the A2Σ+ (v´ = 0) - X2Π (v´´ = 0) transition. The result is of practical importance from the point of view of choosing the optimal scheme for laser excitation of the fluorescence of PO-fragments in the implementation of the method of remote detection of organophosphates.


phosphorus oxide, PO-fragments, absorption spectrum, laser excitation, thermalization, organophosphates


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