Matrix photochheistry of group IIA atoms(M) in the presence of silane:formation and characterization of divalent species HMSiH_3 and univalent MSiH_3
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- 英文论文题名：Matrix photochheistry of group IIA atoms(M) in the presence of silane:formation and characterization of divalent species HMSiH_3 and univalent MSiH_3
- 论文作者：Jie Zhao ; Wenjie Yu ; Peipei Shi ; Tingting Li ; Bing Xu ; Xuefeng Wang
- 英文论文作者：Jie Zhao ; Wenjie Yu ; Peipei Shi ; Tingting Li ; Bing Xu ; Xuefeng Wang ; Department of Chemistry ; Tongji University
- 年：2016
- 作者机构：Department of Chemistry, Tongji University;
- 英文论文关键词：matrix isolation ; photolysis ; excited state
- 会议召开时间：2016-07-01
- 会议录名称：中国化学会第30届学术年会摘要集-第四十四分会：化学动力学
- 语种：英文
- 分类号：O641.1;O644.1
- 学会代码：ZGHY
- 会议名称：中国化学会第30届学术年会-第四十四分会 ; 化学动力学
- 会议地点：中国辽宁大连
- 主办单位：中国化学会
- 学会名称：中国化学会
- 页数：1
- 文件大小：257k
- 原文格式：D
- 会议级别：全国
摘要
It has been known for decades that nsnp excited states of group 2,12,13 atoms can activate C-H bonds or H-H bond.~(1-2)In fact,the first photosensitization reaction studied,in 1923,was the decomposition of H_2 into H atoms by reaction with the Hg(6s6p~3P_1)excited state.~3 There has been wide interest in understanding such fundamental chemical reactions of X-H bonds(where X=H,C,Si,Ge,N,P)activated by M(nsnp)excited states.We report here an investigation of group 2metal atoms(Be,Mg,Ca)with silane in neon and argon matrix.In the reaction of Be with SiH_4,the activation of Si-H bond need the Be atoms been excited.In argon matrix,the resonance transition~1S_0→~1P_1 of Be atoms occurs at 236 nm while the spin-forbidden emission~3P_1→~1S_0appears at 465 nm.Absorptions assigned to BeSiH_3 and HBeSiH_3 increased sharply after full-arc photolysis followed by annealing to 10K again.But nearly no change of spectrum upon>350nm photolysis was observed.It indicates that the reaction of Be(2s2p~1P_1)with SiH_4 dominate the inserting reaction.The participation of 3d orbital in the Ca atom make the reaction channel of Ca+SiH_4 more complicated.Both the absorptions of HCaSiH_3 and CaSiH_3 showed no change upon>500 nm photolysis but increased on>400 nm photolysis.The Ca(4s4p~1P_1)←Ca(4s~2~1S_0)transition of Ca vapor mixed with Ar at 725℃occur at 422.673 nm and spin-forbidden emission Ca(4s4p~3P_1)→Ca(4s~2~1S_0)appears at 657.278 nm.it seems most likely that the formation of HCaSiH_3 in the matrix is brought about by exciting Ca atoms to their~1P_1 state.
It has been known for decades that nsnp excited states of group 2,12,13 atoms can activate C-H bonds or H-H bond.~(1-2) In fact,the first photosensitization reaction studied,in 1923,was the decomposition of H_2 into H atoms by reaction with the Hg(6s6p ~3P_1) excited state.~3 There has been wide interest in understanding such fundamental chemical reactions of X-H bonds(where X= H,C,Si,Ge,N,P) activated by M(nsnp) excited states.We report here an investigation of group 2metal atoms(Be,Mg,Ca) with silane in neon and argon matrix.In the reaction of Be with SiH_4,the activation of Si-H bond need the Be atoms been excited.In argon matrix,the resonance transition ~1S_0→~1P_1 of Be atoms occurs at 236 nm while the spin-forbidden emission ~3P_1→~1S_0appears at 465 nm.Absorptions assigned to BeSiH_3 and HBeSiH_3 increased sharply after full-arc photolysis followed by annealing to 10 K again.But nearly no change of spectrum upon >350nm photolysis was observed.It indicates that the reaction of Be(2s2p ~1P_1) with SiH_4 dominate the inserting reaction.The participation of 3d orbital in the Ca atom make the reaction channel of Ca+SiH_4 more complicated.Both the absorptions of HCaSiH_3 and CaSiH_3 showed no change upon>500 nm photolysis but increased on>400 nm photolysis.The Ca(4s4p ~1P_1)←Ca(4s~2 ~1S_o)transition of Ca vapor mixed with Ar at 725 ℃ occur at 422.673 nm and spin-forbidden emission Ca(4s4p ~3P_1)→Ca(4 s~2 ~1S_0) appears at 657.278 nm.it seems most likely that the formation of HCaSiH_3 in the matrix is brought about by exciting Ca atoms to their ~1P_1 state.
It has been known for decades that nsnp excited states of group 2,12,13 atoms can activate C-H bonds or H-H bond.~(1-2) In fact,the first photosensitization reaction studied,in 1923,was the decomposition of H_2 into H atoms by reaction with the Hg(6s6p ~3P_1) excited state.~3 There has been wide interest in understanding such fundamental chemical reactions of X-H bonds(where X= H,C,Si,Ge,N,P) activated by M(nsnp) excited states.We report here an investigation of group 2metal atoms(Be,Mg,Ca) with silane in neon and argon matrix.In the reaction of Be with SiH_4,the activation of Si-H bond need the Be atoms been excited.In argon matrix,the resonance transition ~1S_0→~1P_1 of Be atoms occurs at 236 nm while the spin-forbidden emission ~3P_1→~1S_0appears at 465 nm.Absorptions assigned to BeSiH_3 and HBeSiH_3 increased sharply after full-arc photolysis followed by annealing to 10 K again.But nearly no change of spectrum upon >350nm photolysis was observed.It indicates that the reaction of Be(2s2p ~1P_1) with SiH_4 dominate the inserting reaction.The participation of 3d orbital in the Ca atom make the reaction channel of Ca+SiH_4 more complicated.Both the absorptions of HCaSiH_3 and CaSiH_3 showed no change upon>500 nm photolysis but increased on>400 nm photolysis.The Ca(4s4p ~1P_1)←Ca(4s~2 ~1S_o)transition of Ca vapor mixed with Ar at 725 ℃ occur at 422.673 nm and spin-forbidden emission Ca(4s4p ~3P_1)→Ca(4 s~2 ~1S_0) appears at 657.278 nm.it seems most likely that the formation of HCaSiH_3 in the matrix is brought about by exciting Ca atoms to their ~1P_1 state.
引文
[1]Steacie,E.W.R.,Atomic and free radical reactions.Van Nostrand Reinhold,New York,1954;Vol.I and II.
[2]Mitchell,A.;Zemansky,M.W.,Resonance Radiation.Cambridge:1934.
[3]Cario,G.;Franck,J.,über sensibilisierte Fluoreszenz von Gasen.Zeitschrift für Physik 1923,17(1),202-212.
[2]Mitchell,A.;Zemansky,M.W.,Resonance Radiation.Cambridge:1934.
[3]Cario,G.;Franck,J.,über sensibilisierte Fluoreszenz von Gasen.Zeitschrift für Physik 1923,17(1),202-212.