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3:18 AM
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Q: Can someone help me understand the motivation behind and visualize the dihedral potential and the Urey-Bradley potential?

megamenceI am studying statistical mechanics and force-fields, and I see a lot of this formula being thrown around with no explanation: $$U_{\mathrm{dihedral}} = \begin{cases} k(1+\cos (n\psi + \phi)),& n>0 \\ k(\psi - \phi)^2, & n=0 \\ \end{cases} $$ The only explanation I read is: this...

0
Q: Why aren't all the fluorescence transitions the same wavelength?

MarkIf all the excited molecules at higher S1 vibrational states rapidly relax to the lowest S1 vibrational state, why do the fluorescence transitions from v' = 1, v' = 2, v' = 3, and other states to v" = 0 have different wavelengths? Why don't they all relax to v' = 0 first and then all transition t...

 
 
1 hour later…
4:32 AM
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Q: Are there any ADME predictions tools available for Python/RDKit?

LeitouranIs there any Pythonic way (a.k.a: a module, an rdkit package, etc) or an API I can use for ADME predictions? I need to prioritize some compounds for purchase/synthesis and some sort of ADME scoring might help me rule out most of them. I am aware of tools like SwissADME but given the amount of com...

 
 
4 hours later…
8:59 AM
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Q: Spurious term in Thomas-Fermi-Hartree energy functional

TheOldJonnyI am quite a beginner in DFT and I am studying the theory behind the computational tools. I have some doubts about the Columb approximate functional term: $U[n] = \frac{1}{2} \int d^3 r \int d^3 r^\prime \frac {n(\mathbf{r}) n(\mathbf{r}^\prime)}{|\mathbf{r} -\mathbf{r}^\prime|}$ If I use the de...

 

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