@LordStryker Nope, no math mode, even if it is very tempting. Everybody goofs now and again, sometimes I come across my own edits and it shoots to my mind: "Mother of Dragons, what was I doing here?!"
It can be rather problematic, and we ask that you do it only when the extended markup is really needed for the meaning of your question in the title. That might be quite often, depending on the questions you ask, we just ask that you consider it.
Titles are a major part of how search engines ind...
@Martin thanks for the tip. I must have missed that memo somewhere. Its easy to put chemical formulas and such in 'text mode' but what about question titles that have actual equations in them?
@LordStryker I always try and go for a more descriptive title, that does not include a formula. In some very rare cases where it is not possible exceptions to the rule are also allowed. In most cases however, you can perfectly transform the title with a few twitches. In the end it should be about readability...
@LordStryker Sometimes it's a real bummer and if I do not even have a clue what some people are asking. Usually the biggest problems make homework questions, where you just would exceed the title field until you get a meaningful question in there. But I figure it is very important, especially when you are later starting to look for duplicates. It's like 'I know there was a question, but I cannot think of the title...' and a very descriptive title comes in handy then...
Well, well, well... it gives you reasonable results in the minimum time required. And after you have initial results you can go all brute force with the ab initio
I would always prefer pm6 over HF/sto-3g, even faster. And you don't even need a basis set. I don't really like the HF approach, DFT at least tries for some coulomb correlation
Ah ha, okay fair enough. But since all the DFT methods are parameterized (i.e. all implementations of DFT suck, er... are fitted to something), then DFT in general is pretty much non ab initio in my opinion.
Exactly, even the cheap methods now need to be calibrated with wavefunction methods (if done properly) completely going against the spirit of DFT in the first place :(
I need someone to back me up on this before I go confront my teacher:
I was doing some analysis of the dipole moment of cis-2-butene.
Let's say that the alkyl groups are both on top.
Would the dipole moment be a vector that has its tail on the top and its head on the bottom?
How would one calcul...
of course the Hessian index from DFT is seriously problematic.
That paper in summary, DFT does good with geoms and energetics with respect to MP2 and CCSD(T), respectively. Massive discrepancies in Hessians, especially for sulfur containing systems.
But I remember M06-2X doing pretty good. TPSS and VSXC pretty much fail across the board.
I know right?! I love these types of questions. Like when someone asked about intramolecular bonding in hydrogen peroxide (?) and I busted out some NBO.
@LordStryker I agree, they do propose a lot of troubles. Unfortunately I am working on copper catalysis... So DFT it is, even if it is right for maybe the wrong reasons
Whenever I am tempted to use B3LYP, I use PBE0, TPSSh and M0X first... then see if anyone wants to argue it is necessary to use that gaussian functional
@Martin I use it just because I know people will want to see it. But honestly it doesn't take that much time to do if I'm already busting out a whole slew of functionals.
On a conference (or talk), if anyone uses only B3LYP I am always tempted to ask: 'Have you verified your results to some other, more reliable functionals?'
@LordStryker Sure I understand, but it would never be the first choice, would it?
You seem to be lucky with a lot of pc power. I have only twenty cores and to big molecules. I can only afford bp86 and have to verify that against other functionals... too bad. I always have to be like, can I skip that?
@Martin I feel ya. Yeah, I'm really lucky indeed to have access to this kind of computer resources. You should move to the southeast (US)! We've got a massive concentration of computing power!
Mini Research Project Time
Preamble
This response is in no way meant to be contrary to what Geoff has already posted. I happen to enjoy these types of questions and I like to tackle them as little research projects for fun. Therefore, my answer will be brutally detailed and in-depth. That sa...
I have recently seen the answer which is locked. What happen to that answer, does it get delete out? Or get opened after some editing by moderators?
Mini Research Project Time
Preamble
This response is in no way meant to be contrary to what Geoff has already posted. I happen to enjoy these types of questions and I like to tackle them as little research projects for fun. Therefore, my answer will be brutally detailed and in-depth. That sa...
The Periodic Table
The Periodic Table