Electronic Absorption and Emission. Lifetimes. Quenching

Absorption spectra of gaseous PH2 [1 to 6] or PD2 [1,2, 7] have been obtained during the flash photolysis (FP) of PH3 or PD3. Absorption spectra of matrix-isolated PH2 [8 to 10] or PD2 

A cw dye laser excitation spectrum of the Oqo Iio line from the subbranch Pi,n i of the 0 0 band revealed the fine structure (electron spin doublet) and also the P hf structure [11]. That study [11] was improved by using an intermodulated fluorescence (IMF) method due to [29]. The hf structure was resolved for 26 lines of the 0 0 band (12 with a total H spin 1(H) = 0 and 14 with 1(H)=1) [12]. 

464 lines due to [5] could be easily identified [14]. For Vg=1 to 4, both and Qq were observed [15], while Qq was not clearly seen in another V2 = 4 spectrum [13]. The V2=4 spectrum in [14] was not analyzed. The V2 = 5 spectrum in [15] showed Qi, the branches Pi N i and P2,n-2. additional features, which were assumed to result from a transition v = 6 V2=1. the spectrum agreed with that in [13], where no assignments had been made [15]. The V2 = 6 spectrum showed only Qi [15]. The heads Qq and from the laser excitation spectrum of PH2 [15] are given in the table below together with the heads from flash photolysis absorption spectra of PH2 and PD2 (apparently Qi values) [1, 2] (all data in A)  

Matrix-isolated PH2 and PD2 absorption spectra showed several bands of the V2=0 progression, shifting by Av to the red. The PH2 bands V2=0 to 7 (Av=62 cm for the 0 0 band) were observed when Ar-PHa (200 1) samples were codeposited onto a 12 K sapphire plate with O atoms (in order to obtain PO2 and PO3 radicals), photolyzed, and annealed [10]. PH2 bands Vg = 0 to 6 (Av ==100 cm- ) and PD2 bands vi = 2 to 9 were obtained when Ar-PH3(PD3) (200 to 500 1) samples were photolyzed in the vacuum UV at 14 K [9]. The bands V2=1 to 5 had been observed earlier after condensing an electrically discharged Ar/PH3 mixture at 4.2 K [8]. Emission 

Lifetimes in vi=1 and 2 are longer for K =1 than for K =0. Renner-Teller coupling between A 2Ai and nonemitting upper vibrational levels of X may be an explanation [15]. - Error limits between 0.5 and 0.9 is higher for vi = 3. - vi=0 excited from vj=1. 

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