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Akef

Member

Registered: 2023-07-15

Posts: 10

Analyzing Electron Density and Bond Characteristics by BCP

Dear Prof Tian Lu
Can we utilize the following information (electron density, Laplacian of electron density, the eigenvalues of Hessian L1-3, charge-shift character, and the electron localization function) to discern the bond strength between Au(I) and the ligands (anion ligand X = Cl, Br, and I and neutral ligand L = OMe2) in XAuL complexes? These values were calculated at the BCP of X-Au and the BCP of Au-L.
If affirmative, could you please elaborate on how we can interpret these results to elucidate the strength of interactions between X and Au, as well as between L and Au?
ρ D^2ρ L1 L2 L3 /\_rel ELF
ClAuOMe2
ClAu 0.112 0.208 -0.123 -0.122 0.452 3.698 0.382
AuOMe2 0.079 0.400 -0.088 -0.085 0.572 6.643 0.131

BrAuOMe2
BrAu 0.101 0.131 -0.099 -0.098 0.327 3.331 0.439
AuOMe2 0.075 0.379 -0.084 -0.081 0.544 6.601 0.128

IAuOMe2
IAu 0.087 0.065 -0.071 -0.071 0.207 2.914 0.502
AuOMe2 0.070 0.347 -0.078 -0.074 0.500 6.567 0.124

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: Analyzing Electron Density and Bond Characteristics by BCP

To distinguish interaction strength via BCP properties, usually you can only compare between same kind of bond. For example, comparing BCP properties for Au-O bond in ClAuOMe2 and AuOMe2. In this case, the larger the electron density at BCP, the stronger the interaction.

Other quantities such as Laplacian of electron density, energy density, eta index and so on, are useful in characterizing covalency. I suggest reading Section "4.A.11 Overview of methods for studying chemical bonds" of Multiwfn manual, which is a overview of commonly studied BCP properties.

Akef

Member

Registered: 2023-07-15

Posts: 10

Re: Analyzing Electron Density and Bond Characteristics by BCP

Thank you very much