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本帖最后由 shiguang 于 2021-1-7 18:20 编辑
8年前老师做了一篇Pd/Ru配合物体系催化Suzuki反应的计算研究，如今想接着研究。（Conjugate Addition vs Heck Reaction: A Theoretical Study on Competitive Coupling Catalyzed by Isoelectronic Metal (Pd(II) and Rh(I)). J. Org. Chem.2012, 77, 17, 7487–7496）当时还是用的高斯03软件包。这是文献里的计算细节：
All calculations were carried out with the Gaussian 03 program package. Molecular geometries were fully optimized with the B3LYP method. The LanL2DZ basis sets with effective core potentials (ECPs) were employed for Pd and Rh, and the 6-31G* basis set was used for H, C, N, O, and P. Harmonic vibrational frequency calculations at the same level of theory were performed to obtain thermal corrections and confirm whether an optimized structure as a minimum or transition state. Single-point energies were calculated using larger basis sets (6-311+G** basis set for H, C, N, O, and P) for Pd(II)(bpy) complexes in order to examine the effect of basis sets. Solvent effects were estimated by the integral equation formulation of the polarized continuum model (IEFPCM), using simple united atom topological model radii with the default parameters for THF. The energies given throughout the paper are Gibbs free energy and enthalpy values computed at 298 K in kcal/mol.
当时计算时用的是B3LYP泛函，对于Pd/Rh，用的是LanL2DZ赝势，其他用的是6-31g(d)，单点能计算用的是6-311+g(d,p)，溶剂用的是THF。
Q1：现在用高斯09应该是选用B3LYP-D3还是选用M06-2X？赝势选择LanL2DZ还是选择SDD对于过渡金属Pd/Ru催化计算更加精确？Q2:这是老师给我的当时计算的gjf输入文件：
%chk=ene-eh-ts.chk
%mem=300mb
#p opt(modredundant,noeigentest,maxcyc=15) b3lyp/gen pseudo=read
Title Card Required
1 1
(分子结构内坐标)
21 30 32 33 F
Pd 0
lanl2dz
****
C H N O 0
6-31g*
****
Pd 0
lanl2dz
(空格)
现在需要进行一步反应过渡态能垒的计算（Pd/Ru配体改变，与原计算任务不同），请问需要怎样更改关键字进行过渡态的搜索？
Q3:这是我写的对初始态进行结构优化的输入文件：
%nprocshared=20
%mem=5GB
#p opt freq b3lyp/genecp scrf=(solvent=thf)
pd-mg
1 1
(坐标)
Pd 0
LanL2DZ
****
H C O N Br 0
6-31G(d)
****
Pd 0
LanL2DZ
(空格)
请问是否有问题？
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发表于 Post on 2021-1-7 17:31:07
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楼主 Author
，现在我也只能靠猜。