The Periodic Table

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06:37

@Wildcat do the bra and ket vectors have to be of the same size? I mean $$\left\langle \Phi\right|\frac{1}{r}\left|\Phi\right\rangle$$ looks fine to me...

1 hour later…

TanMath

07:37

When do you guys use bra and ket vectors in chemistry? For P-chem? @orthocresol

Martin - マーチン

@TanMath just one example... you'll find many more

Q: How to find the second order perturbation to wave function?

Today, I'm looking for how to find the 2nd perturbation to the base in Rayleigh Schrödinger Perturbation Theory (RSPT). SETUP Starting from the 2nd order perturbation in Dirac's notation: \begin{equation} \hat{H}^0 |n^2\rangle + \hat{V} |n^1\rangle = E_n^0 |n^2\rangle + E_n^1 |n^1\rangle +...

TanMath

@Martin-マーチン this looks like pure quantum perturbation theory to me.. where is the chemistry?!

Martin - マーチン

hidden in the lower bottom corner

orthocresol

08:43

Is there anything we can do with answers to homework questions?

-1

A: chemistry lithium

First calculate the number of mols of LiO that you have, which is: number of mols of LiO = mass/molar mass = 25.0/(6.94+2*16.00) = 0.642 mols Then you see that the molar ratio between LiO and Li is 1 to 2 (since 2/4 = 1/2), so to create 0.642 mols of Li you must need 0.642*2 mols of Li. The ma...

Martin - マーチン

08:56

@orthocresol comment and close the question...

and in this case, when it is wrong, downvote.

but i welcome you to open a meta post if you think that is necessary

Wildcat

09:44

=^.^=

\lvert does not work in official mobile app :(

orthocresol

10:20

@Martin-マーチン Hmm, I was just wondering, since we discourage it but if some people do answer then those plain homework questions will continue cropping up. Still, it's only a very small minority of homework questions that get direct answers, so I guess it's fine.

@Wildcat I noticed that this morning ): There is a long workaround: \left\langle \right| \left| \right\rangle with appropriate \vphantom if needed.. I guess plain old | will turn out okay for most people, apart from me :<

@Jan when he got to the $C_{\infty v}$ character table with the $2\cos \phi$, the lecturer just said: "you won't ever really need to use them, so don't worry about them" .___.

Martin - マーチン

@orthocresol this is dirty... use \left\langle ... \middle| ... \middle| ... \right\rangle if you really need it the same size

skill patrol

10:41

OMG @Martin-マーチン you changed your gravatar :O

Martin - マーチン

@Wildcat i works fine in android... must be a bug in the apple app

@skillpatrol I did not change my avatar... I changed my gravatar....

skill patrol

Martin - マーチン

@skillpatrol mwahahahaha

skill patrol

You look very relaxed...

orthocresol

\operatorname doesn't work on the iOS app either if I remember right.

Jan

10:50

@orthocresol $C_{\infty v}$ is damn important! It's HCN's point group D=

Someone should tell the edit suggesting person that it is not common to capitalise compound names in English o.o'

Martin - マーチン

@Jan reject it then

or ping him her in the comments, if you corrected it and the rest of the edit was substantial enough to approve

Wildcat

11:13

Boy, MathJax is painfully slow when there are a lot of formulas. :D

Slooooooooooooooow!

Jan

@Martin-マーチン No, the edits were substantial and an overall net improvement ;) But I accepted and edited.

@Martin-マーチン Why are you so red now? Are you shy and blushing?

Martin - マーチン

@Wildcat try this ... go prepare coffee

Wildcat

I have 249 close votes! I need just ONE MORE!

Jan

@Wildcat SAME D=

Wildcat

Someone, please, close something! :D

Jan

11:16

Or do you want to apply for positions in China @Mart? xD

Martin - マーチン

@Jan nani?

Jan

@Wildcat But not now because it's lunch break time! D=

@Martin-マーチン Your new avatar ;)

Martin - マーチン

what's that to do with china?

Wildcat

@Jan lunch break is for Reviewers only! :D

Martin - マーチン

@Wildcat there should be one you have not voted on...

Wildcat

11:19

@Martin-マーチン zero :(

Martin - マーチン

well sorry then...

@Wildcat May I ask why you use \lvert in your code?

Jan

I got it =D

@Martin-マーチン Just because red is considered lucky in China ;) And because I am once again failing at being funny D=

Martin - マーチン

@Jan ahhh... well yeah, i did not think about that... zorry

skill patrol

@Martin-マーチン thanks for the link pal.

Martin - マーチン

you're welcome :D

skill patrol

11:30

very good

Wildcat

Oh, c'mon! Stupid defaults, burn in hell! Waited for 4 days for a calculation to start running, but forgot the Opt keyword in input file, got single point results. :|

I CLOSED IT! 250 close votes! Gimme badge! :D

You, you, stupid system, gimme my well deserved badge!

skill patrol

badges? we don't need no badges...

skill patrol

11:52

Wildcat

@skillpatrol, nice trolling! XD

skill patrol

@Wildcat I think it's an excellent comparison, even down to the flags :P

Wildcat

=^.^=

skill patrol

Congrats :D

Wildcat

@skillpatrol thanks! :)

Jan

12:21

*highfives fellow reviewer @Cat* *pets @wild, too*

Also, I hit 5 k =D

Wildcat

@Jan, good human! :)

Jan

Human? .__.

pH13

he's a bavarian, not a human

Jan

I'm a vampire, not a human .__.

pH13

close enough

tschoppi

13:01

By the way, I found an acceptable solution for the interim for my problem of checking up on the computation jobs on the cluster: The unix command watch in combination with the option to cumulate the differences. It's not perfect, but currently I don't have time to come up with a different, home-coded solution.

Wildcat

@tschoppi, the only real perfect solution is one that satisfies one's current needs. :)

tschoppi

It doesn't satisfy all my needs, as the diffing is really wonky. But it works for the moment, so I'm gonna keep using it. Especially in combination with tmux

Wildcat

13:52

@Jan, today is The Badges Day! :D

Jan

14:13

So shiny *__*

Yeah, I got a nice answer and enlightened, too *__* As if @cat be my alter ego xD

Wildcat

Jan

15:00

@Wild, if Reviewers are entitled to lunch breaks, does that mean enlightened reviewers are entitled to coffee breaks, too? =3

Wildcat

15:12

@Jan that is a very important question! :D

Jan

15:52

@Wildcat I should ask on meta xD

chemistry.stackexchange.com/revisions/39899/1

Tag choice: priceless.

Wildcat

@Jan deserves to be on the main site, I think! XD

Q: is state of matter a similarity of both solid and liquid?

My teacher put it wrong that solid and liquids do not share state of matter. Yet I look it up and state of matter is something they share, so is it or not something they share?

homework

=o.O=

orthocresol