I read that B3LYP is a hybrid functional which uses some HF method and some DFT method for its calculations. According to this page:(adsbygoogle = window.adsbygoogle || []).push({});

my professor told me that you can set the proportions of each method that the B3LYP uses yourself, so for example you can make it so it uses 70% HF and 30% DFT or 20% HF and 80% DFT etc. I'm trying to figure out how to do that. More specifically, I want to alter the proportion of the HF and slater functionals that B3LYP uses. According to this page: www.gaussian.com/g_tech/g_ur/k_dft.htm [Broken]

the route section for the B3LYP method is as follows:

#P BLYP IOp(3/76=1000002000) IOp(3/77=0720008000) IOp(3/78=0810010000)

I'm confused about what these 3 terms represent. If I wanted to increase the amount of HF that B3LYP uses, what would I change in that route section? In the Gaussian manual, they say that Gaussian can use any model of the form:

P_{2}E_{X}^{HF}+ P_{1}(P_{4}E_{X}^{Slater}+ P_{3}ΔE_{x}^{non-local}) + P_{6}EC^{local}+ P_{5}ΔE_{C}^{non-local}

heres a screenshot of this section of the manual:

Anyone know how I can alter the amount of HF used by B3LYP by altering that route section?

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# Gaussian - Using Hybrid Functionals

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