The Periodic Table

M.A.R.

00:44

Mart's changed his avatar

He's gone feral

Gaurang Tandon

01:32

@M.A.R. it's been like that for a week now I think

Gaurang Tandon

02:41

@hBy2Py yep, and SE is really great at that :)

Gaurang Tandon

04:37

i hope I did the right thing by rejecting this edit - chemistry.stackexchange.com/review/suggested-edits/75465

was pretty weird

Gaurang Tandon

05:23

couldn't this post have been closed as "too broad" instead? chemistry.stackexchange.com/q/92232/5026

i personally don't find it as much opinion based as much as I find it "too broad"

I feel the OP is right in saying that naming conventions would rather be logical than opinion based

Gaurang Tandon

05:37

@AvnishKabaj there?

I got a question in MS Chouhan; Advanced Problems In Organic Chemistry

Tanuj

Hey ! @GaurangTandon

Gaurang Tandon

@Tanuj hi!

Tanuj

@GaurangTandon I've got a question to ask.

Gaurang Tandon

@Tanuj go ahead

Tanuj

This came in my test , If nuclei of a radioactive element is produced at constant rate $\alpha$ and they decay with decay constant $\lambda$ , then at $t=0$ , what is the number of nuclei at time $t$ ?

Haven't really studied anything in modern physics beyond NCERT.

Gaurang Tandon

05:50

@Tanuj you know when no nuclei are being produced, the rate of decay is $dN/dt=-\lambda N$, agreed?

Tanuj

@GaurangTandon yup

lamba LOL

Gaurang Tandon

so, in this case, just add the extra term for alpha, like this $dN/dt=\alpha-\lambda N$

@Tanuj :P

fixed

getting it? ---^

you can then solve this for N

Tanuj

@GaurangTandon okay , why is that ? You know since , I know nothing beyond NCERT level , you'll have to explain even the smallest bits to me

Gaurang Tandon

@Tanuj sure; you know dN/dt is the rate of change of nuclei wrt time; so, when they increase, we have to write $+alpha$ in the RHS (it was given in question: "produced at constant rate alpha")

Tanuj

okay.

Gaurang Tandon

05:53

and we already know the rate of decrease (written with negative sign) is lambda N

cool?

Tanuj

@GaurangTandon yea , seems cool for this question but I'm really not sure about the concept really. I'll need some more practice on this . Can you recommend me some source where I can find more about this ?

Avnish Kabaj

@GaurangTandon yeah sure

Gaurang Tandon

@Tanuj well, idk about any source :/ you can think of it like this way = LHS is the rate of change of nuclei wrt time; change can be either decrease or increase; on RHS we write all the different rates; positive sign means increase and negative used for decrease

@AvnishKabaj see Alcohol, ether, epoxides q20

excess methyllithium on carboxylic acid

ever seen it before?

i haven't

Tanuj

@GaurangTandon alright , thanks.

Avnish Kabaj

@GaurangTandon I'm in 11th

MollyCooL

05:58

Ik this answer was coming lol

Gaurang Tandon

@AvnishKabaj you haven't read the whole of Clayden ?

@MollyCooL i was only hoping because I sometimes feel he's read entire clayden :P

ok nvm, i'll try on main

Avnish Kabaj

@GaurangTandon what no

Gaurang Tandon

@AvnishKabaj oh sorry don't mind!

Avnish Kabaj

Why do you say sorry so much

MollyCooL

Lel! He’s way better than me tho. @AvnishKabaj Associated with FIITJEE?

Gaurang Tandon

06:00

@AvnishKabaj it's all your fault just read the whole clayden and gimme teh answer!!!!!

hehe :P

Avnish Kabaj

@MollyCooL yeah I go to fiitjee

@GaurangTandon after 15 days if it's not answered I'll give you 'teh answer'

MollyCooL

What phase? How much have they done in org?

Gaurang Tandon

@AvnishKabaj you gonna read the clayden in next fifteen days?

MollyCooL

ofc he wont take that much time actually ;P

Avnish Kabaj

@GaurangTandon no my papers gonna finish

Gaurang Tandon

06:02

@AvnishKabaj oh cool

Tanuj

@GaurangTandon Give it a try

in Problem Solving Strategies, 2 hours ago, by Avnish Kabaj

1 hour ago, by Avnish Kabaj

Gaurang Tandon

@Tanuj already did; i've abs no clue

MollyCooL

Cmon! I thought this place is devoid of physics (mechanics atleast) -_-

M.A.R.

06:30

@MollyCooL yes it is. Whoever talks of physics will be crucified to die an agonizing death

Tanuj

@M.A.R. don't say that :(

M.A.R.

@GaurangTandon he's just gonna respond with "and it's SE's goal" and you're gonna respond with "and SE's good at that" and so on

@Tanuj I don't think an online death is really hurtful

Facebook is gonna destroy internet in the near future anyway

Gaurang Tandon

@M.A.R. hehe, yeah, I am boring in my online chat at least

Tanuj

@M.A.R. How can you say when you've never died online before.

M.A.R.

@Tanuj well, at least trying doesn't hurt

Tanuj

06:33

@M.A.R. okay , go ahead

M.A.R.

trying to kill @Tan online

Well, the system does allow me to kill you for one minute

Tanuj

@M.A.R. I mean you kill yourself , why should I take the rism ?

M.A.R.

IOW, kick

@Tanuj I am more important to myself

Tanuj

Okay , I'm real bad at role play , so I'm not even gonna try

M.A.R.

So, how's everyone hanging

Man, 5 reviews left for the next steward

MollyCooL

06:39

Gg

MollyCooL

13:19

Avnish Kabaj

@MollyCooL No u

MollyCooL

Got a doubt!

Avnish Kabaj

@MollyCooL no I don't have any

MollyCooL

Why is temperature not considered while defining standard states for substances? Change in Enthalpy depends on temperature also right?

@any1

Avnish Kabaj

@MollyCooL it's defined for 270 something fixed

MollyCooL

13:28

No

273.15K or 298.15K are usually taken but by definition it strictly is only dependent on pressure

Avnish Kabaj

@MollyCooL Boi <claps hands together> you're talking about standard enthalpy

Right

MollyCooL

13:44

Oh wait sorry for mentionin Bout enthalpy. I was a bit high. I was talking about standard state of a substance

en.m.wikipedia.org/wiki/Standard_state

This one

Avnish Kabaj

13:56

@MollyCooL I 156% doubt that you were high

Gaurang Tandon

@[any-chemdraw-superuser] how much time would it take you to do this chemdraw conversion? (link) I spent exactly 20mins doing this, and am really looking to improve my efficiency, because if I continue at this rate I am in real trouble

can you superusers draw it in shorter time?

[for background, I have <2 months experience on chemsketch]

Avnish Kabaj

@GaurangTandon you pirated chemdraw?

@MollyCooL I guess because

Gaurang Tandon

@AvnishKabaj i said I use chemsketch -_-

1,3-feeds

0

Q: Should the [acid-base] tag be applied to carboxylic acids as well?

This search query yields 33 questions tagged [acid-base] and containing the words "carboxylic acid" in them. (Convenient links to the tag wikis for both [acid-base] and [carbonyl-compounds]) Note that the tag wiki for carbonyl-compounds specifically says: Compounds containing the carbonyl gr...

Avnish Kabaj

Fixing pressure and volume fixes the temp as well?

MollyCooL

13:59

Volume? Where does that come from

Avnish Kabaj

@GaurangTandon that's why that chemdraw'd list was untouched until you dug it up

@MollyCooL the standard state?

MollyCooL

And why is it so? I dont get you

Gaurang Tandon

@AvnishKabaj yeah I think if I increase my efficiency I can counter that list, with one chemdraw conversion per day

Avnish Kabaj

@MollyCooL you're right volume has also not been defined

Ask on maaaaain

@GaurangTandon if I were you I would study in that time

Your mains whatnot is coming

Gaurang Tandon

@AvnishKabaj i know, I was hoping to finish that chemdraw in like 10mins

it took longer

MollyCooL

14:03

Standard state for a material is defined as a reference point to calc properties. That is okay. Now for an ideal gas, only pressure is chosen as 1 bar regardless of temp. But it depends on other macroscopic quantities also right? I mean the refernce point should depend on other quantities also right?

Gaurang Tandon

i know, i'm already back to studies

Avnish Kabaj

@GaurangTandon that's good I should too

Gaurang Tandon

@AvnishKabaj kbye

MollyCooL

Me 3

Avnish Kabaj

Me 4

MollyCooL

14:05

Im like what is chemdraw? Smh

Gaurang Tandon

@MollyCooL a software that helps you draw neat chemical reactions

Avnish Kabaj

@MollyCooL chem draw

Draw chem

Mind blown?

MollyCooL

Like mechanisms?

Gaurang Tandon

yup exactly

MollyCooL

Oh yeah ofc@AvnishKabaj

Good luck, it takes me 10min to even do it on paper

Gaurang Tandon

14:10

hehe

M.A.R.

15:54

@Avnish I think it's best if you leave answering the tag related questions to mods or modlike users

Avnish Kabaj

@M.A.R. ok

M.A.R.

It's not that you'd be wrong or anything

It would get to a consensus faster

LordStryker

16:18

Anyone going to the ACS National Conference in New Orleans next week?

M.A.R.

@LordStryker hello! Who are you?

You seem new to this chat.

Wow, @Lord is sure upset at me for some reason

Avnish Kabaj

@MollyCooL you've misspelled Wikipedia

Gaurang Tandon

for some reason Molly always misspells Wikipedia

idk why

@AvnishKabaj i agree with MAR here; tags are a sensitive issue; i've read literally hundreds of meta posts about homework, and have realized it to be a tough job! it's best to leave deciding tags upto those who've seen it being used for a long time

that's why I didn't touch them myself either

instead left the question on meta

Avnish Kabaj

Ok

I wouldn't add acid base to a question where we weren't talking about acidity/basicity

Gaurang Tandon

@AvnishKabaj yeah I got your point; just leave a comment there instead

Avnish Kabaj

16:32

Sure

M.A.R.

@GaurangTandon how can you misspell Wikipedia?

Wookiepedia?

Avnish Kabaj

Wikepedia

Gaurang Tandon

@M.A.R. not me, but @MollyCooL, always writes "Wikepedia"

M.A.R.

That's a cool misspelling actually

Looks better too

starts spelling Wikepedia as Wikepedia

Gaurang Tandon

ha

M.A.R.

16:35

ah

Avnish Kabaj

note for self Iranians with names starting with m are slightly weird

Gaurang Tandon

you should thank @MollyCooL

M.A.R.

@GaurangTandon I can serially upvote him to get us both suspended

@AvnishKabaj what if I'm the most normal Iranian?

Avnish Kabaj

another note for self weird people think that they're normal

M.A.R.

@AvnishKabaj ha. Weirdo

0

Q: Is Argus lab accurate?

I was trying to calculate the resonance energy of Benzene by using Argus Lab. These values are really weird and highly different from the experimental data.I have several doubts. Q.1 What is the difference between Final SCF Energy and heat of formation? When I tried to calculate the energy, It ...

quantum-chemistry computational-chemistry resonance

Damnit, Indian fellows

There are no such things as doubts.

MollyCooL

16:46

@GaurangTandon @AvnishKabaj omg lmao! Sorry

Gaurang Tandon

16:57

@M.A.R. huh, really? you does not knows engliss!

here at india we even have "doubt classes"

beat that if you can

@M.A.R. well I still have a few questions to post on this site, so would avoid getting even a 24hr suspension

8hr would be ok though, if it's at the time when I sleep

obackhouse

anyone familiar with Psi4?

JavaScriptCoder

not me

quantum chem is not my thing

hBy2Py

20:22

@obackhouse @penta, maybe?

M.A.R.

20:35

@GaurangTandon ugh

pH13 - Yet another Philipp

20:53

@obackhouse the easiest is to simply ask your question

pentavalentcarbon

someone rang

pH13 - Yet another Philipp

@GaurangTandon as I saw it on a question I just answered, simply removing "thank you" from a question is not enough to edit it.

M.A.R.

BEWARE

@KianStevens Thanks for the info. I'm just tired of seeing childish answers (or even teases!) to my technical questions online. Always difficult to find professionals in my research area online. — LittleG 6 mins ago

Might be trolling

Hey @pH13

How are you doing?

pH13 - Yet another Philipp

@M.A.R. hi squared MAR

how are you?

M.A.R.

@pH13-YetanotherPhilipp as miserable as always. You?

@pH13-YetanotherPhilipp you won't dare insult the holy Penrose square

pH13 - Yet another Philipp

21:00

@M.A.R. only you, not the mighty square :D

M.A.R.

You won't dare insult me

pentavalentcarbon

@M.A.R. Your mother was a hamster and your father smelt of elderberries

pH13 - Yet another Philipp

@M.A.R. maybe only throwing tables, not sure

hBy2Py

@ortho, are you in earshot? This question needs locking for a cooldown:

chemistry.stackexchange.com/questions/90381/…

Or, well never mind -- looks like the answer got downvoted enough that OP was able to delete.

M.A.R.

@hBy2Py voluntarily sacrificed to Norse Gods

@pentavalentcarbon that seems to be technically true, unless monkeys evolved in a different branch

hBy2Py

21:07

@pentavalentcarbon ... elderberries are actually rather tasty, when brewed as tea.

M.A.R.

@hBy2Py aww man, I missed drama

pentavalentcarbon

cease your hamster logic at once

M.A.R.

I did it at twice

Just not to do what you say

pH13 - Yet another Philipp

@hBy2Py I still was not able to solve the RR mystery :D maybe sometime in the future

hBy2Py

@pH13-YetanotherPhilipp Were you supposed to be calculating the RR spectrum, or the vibronic fine structure?

pH13 - Yet another Philipp

21:11

@hBy2Py RR

hBy2Py

Because I still suspect (not having read that paper in detail yet) those equations were for vibronics

Raman intensities are a function of the polarizability derivatives with respect to normal mode displacements

pH13 - Yet another Philipp

@hBy2Py at least the paper from Guthmuller is about calculating RR spectra with different assumptions. I'm quite sure about this.

hBy2Py

$\partial^3 U \over \partial E^2 \partial Q_i$

How in the world $d\Omega\over d q_i$ would map to that... I have no clue

pH13 - Yet another Philipp

a lot of mysteries to get solved by me :)

M.A.R.

You only know the basic stuff

pH13 - Yet another Philipp

21:16

@M.A.R. like 1+1, indeed

Mithoron

Hullo

M.A.R.

@Mithoron hey

@pH13-YetanotherPhilipp that's acidic

pH13 - Yet another Philipp

@M.A.R. not if it is pOH

M.A.R.

Who uses stuff like that?

pentavalentcarbon

@obackhouse yes

pH13 - Yet another Philipp

21:22

@M.A.R. that's not the point

M.A.R.

@pentavalentcarbon yes!

@pH13-YetanotherPhilipp the equivalence point?

-1

Q: organic chemistry benzoic acid

resonance structure for benzoic acid and why the second one is resonance https://www.quora.com/What-are-the-resonance-structures-of-benzoic-acid

acid-base

2

Q: Lets clean up this backlog of unanswered questions

The Problem As explained in this post and a follow-up to this one: Obviously the event linked did a lot to clean up unanswered questions, but there is still a long way to go! Statistics for my favorite sites (unanswered with no upvoted answers): $\pu{\color{Green}{13} Worldbuilding}$ $\pu{\c...

discussion chat unanswered-questions

Loong

@M.A.R. someone please remove that abusive MathJax from that question :-(

M.A.R.

@Loong shh Mart might hear it

pH13 - Yet another Philipp

@penta could you find out why the MO cubes looked so strange?

M.A.R.

Comments are not for extended discussion; this conversation has been moved to chat. — Loong ♦ 10 mins ago

Bestest thing anyone could have done on that discussion like thing

pentavalentcarbon

21:29

@pH13-YetanotherPhilipp no, I can't be bothered right now, my thesis defense is in a week

but I'll probably do it before I get to the Molpro thingy

M.A.R.

@pentavalentcarbon oh boy

Just keep remembering the best and worst things that could happen

pentavalentcarbon

also MOs are stupid, I hate them with a fiery passion

M.A.R.

The emotional tide would settle down

@pentavalentcarbon you can't set fire to MOs

pentavalentcarbon

it's fine, my practice talk was total dog shit, so standard fare

pH13 - Yet another Philipp

@pentavalentcarbon then good luck!

pentavalentcarbon

21:30

ohohohoho that's where you're wrong, kiddo

M.A.R.

The closest you get is burning the computer

pH13 - Yet another Philipp

@M.A.R. or making a nice animation with Blender or sth like that

pentavalentcarbon

Well, I've come close many times. Many, many times.

M.A.R.

And I wouldn't do that because of Microsoft solitaire

pentavalentcarbon

Microsoft? vomits

M.A.R.

21:32

Ha, mission accomplished

pentavalentcarbon

I have so many software hills I will die on, and that is the biggest

1,3-feeds

-4

Q: Is this website for professional chemists or school pupils?

Just come here. Can't figure out what this website for. If it's for students' homework, then I'll go away.

discussion

1

Q: Lets clean up this backlog of unanswered questions

The Problem As explained in this post and a follow-up to this one: Obviously the event linked did a lot to clean up unanswered questions, but there is still a long way to go! Statistics for my favorite sites (unanswered with no upvoted answers): $\pu{\color{Green}{13} Worldbuilding}$ $\pu{\c...

discussion chat unanswered-questions

M.A.R.

The hill from your vomit?

@1,3-feeds shoo you stupid bot

pentavalentcarbon

@M.A.R. ohhhhhh you're really good today!

M.A.R.

@1,3-feeds Can't you see we're having a serious adult discussion?

pentavalentcarbon

21:34

Anyway, if backhouse comes back you can ping me, I think they're in England so I wouldn't expect it

M.A.R.

@pentavalentcarbon My BP after dialysis was 8.5

pentavalentcarbon

@M.A.R. Serious adult discussion? vomits

M.A.R.

And I'm making up for it

@pentavalentcarbon you should really have your food checked

I haven't put the poison in it yet

So that means someone beat me to it

Who else has 4 Stewards?

Probably just ron and Todd

Ha, somehow I haz the most gold badges on Chem

Next is Manish, 10

I'm pretty lacking in silver though

M.A.R.

22:26

-1

Q: I need help with coming up with an inquiry question & hypothesis in chemistry... the following questions need to include ... (listed down below)

The following question must include: ONLY PURE SUBSTANCES The inquiry question should compare at least ONE PHYSICAL PROPERTY in TWO different substances or TWO PHYSICAL PROPERTIES in ONE substance. Should only be 1-2 lines The question must be REPRESENTED IN A MODEL outlining the strengths of...

physical-chemistry bond ions atoms intermolecular-forces

Yes ma'am. Of course ma'am. Would you like to listen to some music while you wait?

obackhouse

23:01

@pentavalentcarbon I was wondering if there was a way to make Psi4 print out the two-electron derivatives when calculating analytical hartree-fock gradients

Needed it for a test case before - don't need it for that reason any more but would be nice to know

In other news - I've finally implemented analytical gradients into my hartree-fock code....... too many hours debugging

Now I just need to replace this garbage steepest descent algorithm heh

pentavalentcarbon

23:27

import numpy as np
np.set_printoptions(precision=5, linewidth=200, suppress=True)
import psi4

# Memory for Psi4 in GB
psi4.set_memory('500 MB')
psi4.core.set_output_file("tei.out", False)

mol = psi4.geometry("""
O
H 1 1.1
H 1 1.1 2 104
symmetry c1
""")

psi4.set_options({'basis': 'sto-3g',
                  'scf_type': 'direct'})

wfn = psi4.core.Wavefunction.build(mol, psi4.core.get_global_option('BASIS'))
mints = psi4.core.MintsHelper(wfn.basisset())

# Get nbf and ndocc for closed shell molecules

I is the desired 4-index tensor

for $(\mu\nu|\lambda\sigma)$, that is

obackhouse

wonderful, thanks man

pentavalentcarbon

Ya, feel free to ping me in chat if you have any more questions...

if you want a better optimizer, this may be interesting (haven't tried it myself): github.com/azag0/pyberny

obackhouse

23:43

never seen that before - I think I'm just gonna write my own conjugate gradient alg

I've written the entire program myself (except the linear algebra) so trying to keep it that way

I know Gaussian uses the berny algorithm a lot

but i don't fancy writing in 2nd order analytical derivatives

not sure I'm quite at that level yet haha

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