第二讲溶剂效应.ppt

第二讲溶剂效应溶剂效应有时甚至使气相分子的精确计算结果失去定性意义!!!1.超分子方法(microscopic)
solute-solventsystem:

构象问题,
计算量问题,
外部溶剂的板块效应问题.溶剂性质
介电常数e
极化电荷
孔穴表面
介质无结构
各向同性(稀溶液)
各向异性(液晶)
优点:计算量小,使用方便
缺点:缺乏溶质-溶剂相互作用的微观信息,如氢键3.超分子-连续介质方法溶剂化能平衡溶剂化平衡溶剂化和非平衡溶剂化CPL，255，327（1996）1.连续介质模型球孔穴的Born公式(点电荷模型)球孔穴的点偶极模型-Onsager模型1)溶剂化能2)极化面电荷3)自洽反应场(SCRF)Onsager
Self-Consistent
ReactionField(SCRF)WaterorH2O:ε=78.39,AcetonitrileorCH3CN:ε=36.64
DiMethylSulfoxideorDMSO:ε=46.7
MethanolorCH3OH:ε=32.63,EthanolorCH3CH2OH:ε=24.55
Isoquinoline:ε=10.43,Quinoline:ε=9.03
ChloroformorCHCl3:ε=4.9
EtherorDiEthylEtherorCH3CH2OCH2CH3:ε=4.335
DiChloroMethaneorMethyleneChlorideorCH2Cl2:ε=8.93
DiChloroEthaneorCH2ClCH2Cl:ε=10.36
CarbonTetrachlorideorCCl4:ε=2.228
BenzeneorC6H6:ε=2.247,TolueneorC6H5CH3:ε=2.379
ChloroBenzeneorC6H5Cl:ε=5.621
ChroMethaneorCH3NO2:ε=38.2
HeptaneorC7H16:ε=1.92,CycloHexaneorC6H12:ε=2.023
AnilineorC5H5NH2:ε=6.89,AcetoneorCH3COCH3:ε=20.7
TetraHydroFuranorTHF:ε=7.58
DiMethylSulfoxideorDMSOorCH3SOCH3:ε=46.7
ArgonorAr:ε=1.43,KryptonorKr:ε=1.519
XenonorXe:ε=1.706
Abinitiostudiesonthemechanismofthecycloadditionreactionbetweenketeneimineandformaldehyde-catalyticandsolventeffects2[1+1]FurfuraldehydeconformationalequilibriumDipoleformulacanbegeneralizedfor
higher-orderelectrostaticterms:FurfuraldehydeconformationalequilibriumRivailandRinaldi(QCPE1992)RivailandRinaldi(QCPE1992)RivailandRinaldi(QCPE1992)RivailandRinaldi(QCPE1992)UA0，UAHF，BONDI,UFFetc.MuWH，ChasseGA，FangDC，Int.J.QuantumChem.,108,14221-434(2008)ComputationMethodVanderWalls’radiiSolvent-accessiablesurface(SAS)solventeffectRIF？SCRFMETHODSCRFMethodExternalforceforoverestimationof~20kcal/molinteractionenergyreasonAtomAtomJPCA,2008,112,6708THEOCHEM,2007,806,1712ar/2a=3:2Energy
FreeenergyEntryStereo-selectivityforR2=Ph1.45ForR2=hexyl