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T Janati

Publications and source records attributed to T Janati.

4 recordsLinked to original sources

Partial pressures and nature of products. Application to the photolysis of PH3 and NH3 in the atmosphere of Jupiter and Saturn.

The photolysis of mixtures of gases containing NH3 or PH3 presents important differences mainly due to the strength of the X-H bond. On some examples, these differences are evidenced and the consequences for mixtures of gases containing these two compounds are shown: the photolysis of ammonia and ethylene mainly gives ethyl-, butyl- and hexylamine whereas the photolysis of phosphine and ethylene leads to ethyl- and vinylphosphine. When gaseous mixtures of NH3, PH3 and ethylene are photolyzed together, the presence of phosphine dramatically decreases the formation of nitrogen derivatives. The relevance of such lab studies to the atmospheres of Jupiter and Saturn is discussed.

Amines↗

Photolysis of phosphine in the presence of acetylene and propyne, gas mixtures of planetary interest.

Phosphine (PH3) 1 has been observed in the atmospheres of Jupiter and Saturn. We have studied the photochemical reactions of this compound with acetylene (C2H2), an alkyne also detected in these atmospheres. The volatile products formed in these reactions were characterized by H, 31P and 13C NMR. The ethenylphosphine 2 is the first product formed in the photolysis of PH3 in the presence Of C2H2. Photolysis of PH3 in the presence of propyne (C3H4) led to the formation of the Z- and E-prop-1-enylphosphines and traces of 1-methylethenylphosphine. A reaction pathway is proposed. The initial step is the dissociation of PH3 to hydrogen and PH2 radicals. Addition of the phosphinyl radical on alkyne occurs as the next step. Vinylphosphines are then formed by radical combination. This proposed reaction pathway takes into account the nature of the products and studies devoted to the photolysis of germane (GeH4) or hydrogen sulfide (H2S) in the presence of alkyne. Attempts to detect the methylidynephosphine HC triple bond P (the isoelectronic compound of HC triple bond N), in the photolysis products of PH3-C2H2 mixtures were unsuccessful. The application of these findings to Jovian and Saturn atmospheric chemistry is discussed.

Acetylene↗

Germane photochemistry. Photolysis of gas mixtures of planetary interest.

Photolysis of germane (GeH4) in the presence of acetylene (C2H2), propyne (C3H4) or phosphine (PH3) with a 185 nm mercury lamp has been studied. The volatile products formed in these reactions are characterized by 1H, 31P and 13C NMR. Vinylgermanes are the first reaction products formed in the photolysis of GeH4 with alkynes. A reaction pathway is proposed. The initial step is the dissociation of germane 1 to hydrogen and GeH3 radicals. Addition of the germyl radical on alkyne is proposed as the next step. Vinyl-germanes are then formed by radical combination. Photolysis of ethenylgermane 2 gives diethenylgermane 3 in the presence of acetylene and digermaethane 4 in the presence of GeH4. The application of these findings to Jovian and Saturn atmospheric chemistry is discussed.

Acetylene↗