Reactions involving the formation and transformation of H3+

40 Pages·2015·1.51 MB·English

by  Octavio Roncero

Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Reactions involving the formation and
transformation of H+
3
Octavio Roncero
Inst.F´ısicaFundamental,CSIC
[email protected]
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Outline
1 Introduction
2 H+ PES’s
n
3 H2+H+3 exchange reaction
4 H2+H+2 direct reaction
5 Conclusions
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Molecular Universe
Hollenbach&Tielens,Annu.Rev.Astrophys.(’97)
Stellaratmosphere:
PDR Molecularclouds
atomiclines
FormationofH lowtemperatures
Atom+Atomcollisions 2
actasshieldforother varyingdensities
Magneticfields
molecules formationofcomplex
Polarizationoflines M+ +H →MH+ +H molecules
2
Hanleeffect M+H+ →MH+ +H
3 2
OctavioRoncero TCSMD,Dalian,June2-6th2015
ThemostabundantionisH+
3
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Chemical pumping in molecular clouds and PDR’s
ExothermicreactionsofH withatomsandions
2
H (v =0)+O+ →OH+(v(cid:48),j(cid:48))+H
2 Go´mez-Carrasco,etal.ApJ,(’14)
ChemistryofH (v >0)inISM
2 Agu´ndez,etal.ApJ,713,662(’10)
Initialstatedependentchemistry
H (v =1)+C+ →CH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.ApJ,766,80(’13)
H (v >1)+S+ →SH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.AJ,146,125(’13)
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Chemical pumping in molecular clouds and PDR’s
ExothermicreactionsofH withatomsandions
2
H (v =0)+O+ →OH+(v(cid:48),j(cid:48))+H
2 Go´mez-Carrasco,etal.ApJ,(’14)
ChemistryofH (v >0)inISM
2 Agu´ndez,etal.ApJ,713,662(’10)
Initialstatedependentchemistry
H (v =1)+C+ →CH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.ApJ,766,80(’13)
H (v >1)+S+ →SH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.AJ,146,125(’13)
ThemostabundantionisH+
3
-H+ disappearsrapidlyintheexothermicH +H+ →H++H reaction
2 2 2 3
-HoweverH +H+ →H++H
2 3 3 2 (ortho/paraconversion,deuteration)
-H+ isveryreactivewithotherspecies:
3
H++O →H +OH+
3 2
H++O →H +O H+
3 2 2 2
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Chemical pumping in molecular clouds and PDR’s
ExothermicreactionsofH withatomsandions
2
H (v =0)+O+ →OH+(v(cid:48),j(cid:48))+H
2 Go´mez-Carrasco,etal.ApJ,(’14)
ChemistryofH (v >0)inISM
2 Agu´ndez,etal.ApJ,713,662(’10)
Initialstatedependentchemistry
H (v =1)+C+ →CH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.ApJ,766,80(’13)
H (v >1)+S+ →SH+(v(cid:48),j(cid:48))+H
2 Zanchet,etal.AJ,146,125(’13)
ThemostabundantionisH+
3
-atlowTmoleculesfreeze
-H+ “lives”longertime
3
-H Deuterationoccurs
3
-KeyprocessforhighD/H
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Previous studies on H+.
4
Experimental
H +H+(v =0−3)→H+ +Handisotopicvariants
2 2 3
Koyano&Tanaka(’80);Andersonetal.(’81),Krenosetal.(’76),...
H+ infraredspectra,producedinthepreviusreaction
3
Carrington&Kennedy(’84);...
Simulationofthepotential
Diatomics-in-Moleculespotential
Muckermanetal.(’81)
PESwithfrozenH+
3 Alvarez-Colladoetal.(’94)
InterpolatedPESintheH+H+ channel
3 Moyanoetal.(’04)
StationarypointsandintersectionsalongtheMEP
Varandas(’08)
NoaccurateglobalPESavailable
H+ +H →H+ +H collisionsimulations
2 2 3
Quasi-Classicaltrajectories,withSurfacehoppingusingDIM
Stine&Muckerman(1976,...);Tully&coworkers(1976,...);Schatz&coworkers(1985,...);...
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
H + H+ exchange collision: ortho/para conversion
2 3
QCTcalculations:Moyano&Collins,(’03)
7DQuantumWPwithreduceddimensions:Bowman&co.(’10)
Statisticalapproachesincludingspinstatistics:
Park&Light(2007) Hugoetal.(2009) McCalletal.(2011)
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Objectives
Full dimensional PES for H+ and H+
4 5
with good long range behavior
with analytical derivatives and non-adiabatic couplings
H + H+ → H++H Is the reaction statistical?:
2 3 3 2
Going beyond pure statistical approach
Parker&Light(’07),Hugoetal.(’09)
- Introduction of dynamical bias
- Use global PES
Comparison with experimental Khop/Kexchange
McNabandcoworkers(’11)
H + H+ → H++H
2 2 3
Non adiabatic couplings and Conical intersections
Non adiabatic dynamics: MD with Quantum Jumps
Tully(’90)
OctavioRoncero TCSMD,Dalian,June2-6th2015
Introduction H+nPES’s H2+H+3 exchangereaction H2+H+2 directreaction Conclusions
Outline
1 Introduction
2 H+ PES’s
n
3 H2+H+3 exchange reaction
4 H2+H+2 direct reaction
5 Conclusions
OctavioRoncero TCSMD,Dalian,June2-6th2015