The Periodic Table

user116211

04:39

@Loong SE runs its its seasonal feats this way.....

user116211

At the time of the launch, there was, in any place of the earth, April 1, maybe Mart's?

IͶΔ

06:32

@MAFIA36790 Hawaii

IͶΔ

06:53

0

Q: kinetics of adsorption of hydrogen on nickel

What is the order of reaction involving adsorption of Hydrogen on Nickel? The reaction does not depend on the concentration of hydrogen (does it?) but depends on the surface area of nickel. More the surface area, more is the rate of adsorption. So does the rate law depend on Nickel? How can I fi...

Hmm, zero order is only is special circumstances @Aditya.

The rate law differs in different situations, AFAIK.

user116211

07:06

@IͶΔ: o/

IͶΔ

\o

user116211

@IͶΔ Mart is in Hawaii?

IͶΔ

No, April fool first begins in Pacific islands

user116211

@IͶΔ oh.

user116211

@IͶΔ: yesterday, I bought a new phone....

IͶΔ

07:09

So that's why you weren't in chat full-time. :P

user116211

@IͶΔ No....

IͶΔ

Admit it now, you're BUSTED

user116211

I was really busy with my studies....... I had world cup match to see at the night...... I had to complete the lectures .... it was reeeaaaaallllly a busy day.....

IͶΔ

BTW did England win the cup?

user116211

@IͶΔ Damn, don't tell me again about this.... I want to forget this hoooorrrrroorrrrr ;(

user116211

07:12

BTW, final is in April 2.

IͶΔ

Aha.

I'm betting 2 upvotes that England is gonna win.

user116211

Ind is not in the final.... I've no interests left......

user116211

However, I'll update the result to Mart.....

IͶΔ

What is the other side in the finals? Germans?

user116211

@IͶΔ Germans don't play cricket ;P

user116211

07:20

Well, they have a team but they are not officially recognised by ICC as a test nation.

user116211

@IͶΔ West Indies v England.

Martin - マーチン

10:29

so england is going to take home the trophy then... i guess people will get especially drunk that night in the pubs lol

user116211

@Martin-マーチン Their damn pub culture.....

user116211

WI have defeated them in Qualifiers....

user116211

but that was a different pitch....

Martin - マーチン

10:42

well everything changes in tournaments...

user116211

I've not a little interest left, so....

user116211

I don't care.

user116211

::sigh::

Martin - マーチン

sorry to hear that... but it happens to all of us, when the favourite team leaves the tournament...

user116211

@Martin-マーチン Thanks...

user116211

10:47

call it luck or what...

user116211

But Ind were the pre-favourites to win the cup....

Martin - マーチン

well maybe bad luck... next time ;)

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Pakistan is out?

user116211

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ Ha! YES!!

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Wow!

user116211

10:49

Ind whitewashed Aus in their own den; defeated Sri Lanka; won Asia cup....

user116211

and then....

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

You can't stay hot for too long.

Especially with injuries.

user116211

in the crucial semis, you get rid of the most annoying player but it turns out to be no ball....

user116211

not one, two but THREE times, a man was out but for delivering no balls, he took away the semis :(

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Is betting allowed?

user116211

10:53

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ Not in India.

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

That will keep the sport clean.

@MAFIA36790 are the players drug tested?

user116211

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ don't know about the details but yes; they are very strict.....

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

What was the last scandal about? @MAFIA36790

user116211

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ IMO, you are talking about the IPL spot-fixing scandal?

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Yup.

user116211

11:05

2013 Indian Premier League spot-fixing and betting case

The 2013 Indian Premier League spot fixing and betting case arose when the Delhi Police arrested three cricketers, Sreesanth, Ajit Chandila and Ankeet Chavan, on the charges of spot-fixing. The three represented the Rajasthan Royals in the 2013 Indian Premier League. In a separate case, Mumbai Police arrested Vindu Dara Singh and Gurunath Meiyappan for alleged betting and having links with bookies. == Investigation details == Sreesanth was arrested at his friend's house, whereas Chandila and Chavan were arrested from their team hotel in Mumbai. Rajasthan Royals suspended the contracts of the three...

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Thanks for the link.

user116211

@Brian: o/

Brian

I guess my 'center of charge' explanation was essentially correct then, @Mart?

4

A: What are dipole moments in a molecule supposed to act upon?

Your confusion appears to arise from trying to consider dipole vectors as representing forces, which is incorrect. Dipole vectors don't "act on" anything; they describe the displacement of the "center-of-charge"‡ of a given region of space (including both the electron cloud and the nuclei) from ...

I suddenly realized after OP asked about it that I didn't have as firm a grasp on it as I thought!

@MAFIA36790 Japan, I thought.

Martin - マーチン

@Brian correct

@Brian also correct

The whole centre of charge is a bit fuzzy though...

Brian

I mean, one can find the centroid of charge pretty readily from the nuclear positions and the density distribution, right?

Martin - マーチン

11:11

for neutral molecules, it doesn't really matter where you put 0,0,0... but when you go to charged species... things are different

@Brian yes

Brian

<nod>, because the dipole of a charged species relative to a point at infinity is the infinite vector (or somesuch)?

Martin - マーチン

yes

it depends on the reference point...

that is why for ions you should probably pick the centre of mass for reference

makes calculations difficult though

especially for non-symmetric molecules...

Brian

<nod>

Martin - マーチン

i had a problem with that question, since the misconception was basically treating electrons as separate bodies

Brian

The atom-pairwise dipoles are ambiguous, right? Because you have to rely on (~arbitrary) selection of a charge partitioning scheme? (Mulliken vs Löwdin vs Bader vs Hirshfeld vs ...)?

@Martin-マーチン Yeah, and it assumed the dipole vectors were acting on the system, rather than describing it.

user116211

11:16

I may be bit stupid to ask that but how many p orbitals are there in triene?

Martin - マーチン

@MAFIA36790 you mean how many form the pi system?

user116211

user116211

@Martin-マーチン No. p and pi are not same, I guess ;P

user116211

Are there 6 p orbitals?

Martin - マーチン

@Brian yes they are...

user116211

11:18

At least my book says so (March's Organic)

Martin - マーチン

i did löwdin charges... but i was reluctant to include them, because i did not have the time to check it... but they put the negative charge on the carbon O.o

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Hi @Brian :-)

Brian

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ <tips hat> :-)

user116211

@Martin-マーチン At first, I thought so.... but six?

Martin - マーチン

@MAFIA36790 one per carbon

they form the pi system, it's delocalised

user116211

11:19

@Martin-マーチン got it.

Brian

@Martin-マーチン Yeah. I don't trust Mulliken or Lowdin for anything other than consistency checking between calculations

The logic behind Bader's QTAIM really appeals to me.

Martin - マーチン

yeah it really does... i think these are the most reliable charges, since the basins are well defined and real

and you can in theory get the electron density from experiment and compare

user116211

I was reading about cross-conjugation.... then I read ron's answer but didn't get the crux of the point.....

Brian

<nod> I've read a couple of papers where people have actually done it.

Martin - マーチン

it's a bit tedious when the system becomes huge

user116211

11:22

okay, if six p orbitals are participating, then there must be 6 MOs....

Brian

@Martin-マーチン <chuckle> Most definitely. But, then, most quantum methods get tedious when the system becomes huge. :-)

user116211

Doing SHO, three lowest BMOs are $$\alpha + 1.932\beta\\ \alpha + \beta \\ \alpha + 0.518\beta$$

pH13

@Brian QTAIM charges are not in all cases able to reproduce the ESP, what ... as far as I read it ... a good charge method should be able to do

user116211

Does cross-conjugation mean that two of the $\ce{C}$ in triene don't participate in the $\alpha + \beta$ orbital formation?

user116211

I think that is what it means as cross-conjugation when one of the three pi systems do not participate in conjugation?

Brian

11:28

From CO2 optimized at PBE/def2-TZVP with RI, using ORCA keywords !TIGHTOPT GRID4 GRIDX4; QTAIM by MultiWFN 3.3.7, "medium" density integration grid:

O: 9.142 --> -1.142 net charge
C: 5.407 --> +0.593 net charge on each

The medium grid is too small, which is why the net charge isn't exactly zero.

@pH13 Ah, right, that's what the main gripe was.

QTAIM can, you just have to carry out the multipole expansion to several terms.

It's just less convenient than other partitioning methods specifically constructed to give good ESPs in fewer terms.

Ok, I'mma be late for work if I don't... <disappear>

Martin - マーチン

well the quality of AIM charges depends on the use QC method

pH13

@Martin-マーチン I'm no expert on this, but I don't think that this holds for population analysis with aim stuff

Martin - マーチン

why not?

If your wave function is crap, your charges are bollocks

2

pH13

@Martin-マーチン because paper ...

because of reasons. very good reasons. period.

Martin - マーチン

lol...

never trust anything, ever, numbers lie, always

pH13

11:36

I trust my new gold stand HF/STO-3G ... no need to change

user116211

12:24

1

Q: How dependent are computed charges using the quantum theory of atoms in molecules on the used level of theory?

The quantum theory of atoms in molecules is based on the topology of the electron density. This mathematical analysis allows to find critical points and hence has a unambiguous way of separating a molecule into atoms. Each atom can be assigned a basin, and integrating the electron density in it y...

quantum-chemistry computational-chemistry

user116211

@Mart also asks question ;p

Brian

12:47

Waitaminute

I just calculated OC2, not CO2. D'OH.

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

Welcome back

Brian

@pH13 Concur, generally. The density distribution converges much faster than most other properties, as I understand it.

Of course, if the WF is complete garbage, then you can get fouled results, but as long as you're not using, e.g., HF on a nickel Werner complex you're probably ok.

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ Thanks! (sorry for time lag, running around a bit here)

Sᴋᴜʟʟ ᴘᴇᴛʀᴏʟ

13:03

np, we're used to this asynchronous communication device :-)

Brian

@Mart Values for CO2 (and not OC2) with the MultiWFN 'medium' grid are:
O: 8.987 --> -0.987 at each atom
C: 3.967 --> +2.031

Charge neutrality is achieved at this grid to within 0.06 electrons, so not too bad.

@Sᴋᴜʟʟᴘᴇᴛʀᴏʟ Indeed. The ability to link things as replies to specific prior points in the conversation is amazingly handy.

Martin - マーチン

well, that matches my results

Brian

@Martin-マーチン But there are still ~7% differences, despite us both using pure functionals and triple-zeta bases.

So, yeah, looks like it does matter.

Martin - マーチン

well accuracy \pm0.1

Brian

The figures in the Chinese paper that @pH13 linked to in his comment make it pretty clear that there are definitely method effects, and not always systematic.

AFAIK there is no english version, but Lu and Chen, Acta Phys Chim Sin 2012, 28 (1), 1-18 cover that question for quite a few methods. — pH13 44 mins ago

pH13

13:20

@Brian I commented it already ... but I found that paper while reading the multiwfn manual :)

A chinese friend helped me reading most parts of this paper.

Brian

@pH13 Sounds like you're well-equipped to answer @Mart's question, eh?

pH13

but I have no time to do so :)

another story ... @Brian have you ever tried the gCP correction in ORCA?

Brian

@pH13 Yes, I've used it in a variety of calculations, but I haven't done any systematic analysis on how well it performs.

Also, the analytical Hessian for it for some functionals seems to be broken.

pH13

13:46

@Brian it seems for me, that I can't use it together with RI or ECP ... do you know more?

Brian

13:59

@pH13 Never tried it with ECP. I almost always use RI/RIJCOSX, so I don't think I've had problems there.

Are you using v3.0.3?

pH13

@Brian yes

! b3lyp def2-tzvp rijcosx def2-tzvp/j ecp{def2-tzvp,def2-tzvp/j}
! d3bj gcp(dft/tz) opt tightscf grid5 gridx5
! cosmo(acetonitrile) pal8

Brian

14:28

@pH13 I've used essentially that input before, minus ECP and COSMO, and it's worked fine.

It wouldn't surprise me if ECPs fouled it, though.

Is it throwing errors? Or just outputting nonsense?

pH13

ERROR: Number of atoms in ORCA and otool_gcp are different:
ORCA: 68  gCP: 0
NOTIFICATION: Different basis set in ORCA and otool_gcp:
ORCA: 1448  gCP: 133110635
If you are NOT using ECPs, check your basis set inputs!
------------------   -----------------
gCP correction             0.000000000
------------------   -----------------

@Brian

no super table flips anymore for @IͶΔ ... :C

IͶΔ

!!table

(╯°□°）╯︵ ┻━┻

pH13

besides that ... I need !!kannadeyes

IͶΔ

(╯ಠ_ಠ）╯︵ ┻━┻

pH13

!!kannadesk

Brian

14:51

@pH13 Do you have any light atoms in your system? Or are they all ECP atoms?

pH13

Ru, Cl, C, H, F, O

but as always I cannot post the structure

Brian

@pH13 Do you have any ghost atoms, dummy atoms, or point charges? The "ERROR: Number of atoms in ORCA and otool_gcp are different:" bit is concerning.

Can you post the full input file, minus the structure?

pH13

@Brian only %maxcore and *xyz 0 1 follows

Brian

@pH13 Mm. Try pulling D3BJ and GCP(...) up into the first simple input line.

gCP{...} may have some special concurrent parsing interactions with the ECP{...} keyword. As you have it now, gCP may not realize there are ECP substitutions happening.

pH13

@Brian let's see

is there a limit for commands per line?

do you know that?

Brian

15:01

@pH13 Mmph.... probably? But I've never run into it.

Some string length limit

But only the ORCA devs would know.

pH13

gosh ... I hope they will fix such stupid things in future :) ... also when will the next release come? :C

yesterday was frank neese day in orca forum ... was funny to see

Brian

@pH13 I actually did a deep dive into the simple input parsing. I personally am glad that it works as well as it does.

It would be brutal to have to enter everything in block syntax.

Gaussian's input syntax isn't much better. I mean, IOp this, and IOp that... guh.

<nod>, he drops in periodically

I almost wonder if that's a sign that a new release is coming soon.

IIRC, the last time he dropped in one of the v3.0.x releases came shortly thereafter.

pH13

@Brian right ... :D but then they don't care for multiple lines for their command line

Brian

Frank Neese, Quantum Santa Claus

pH13

:D

Brian

15:05

@pH13 One of the nasty things to watch out for with ORCA, too, is order of parsing on the simple input lines.

Primarily, if you specify an [x]SCF keyword on the same line as, or on a previous line relative to, either an [x]OPT keyword or NUMFREQ (but not ANFREQ), the convergence tolerances get reset to TIGHTSCF.

pH13

@Brian I printed this a few weeks ago to have it offline :D

Brian

I do most of my production work at VERYTIGHTSCF, so I have to make sure that I always put it in the right place.

pH13

only extremescf is more funny

Brian

@pH13 I'm glad you find it useful!!

I'm surprised that such documents aren't published by more software packages, and verified to be accurate with each new release.

I mean -- just like any experiment, you want to be sure your parameters are, in fact, what you think they are.

pH13

@Brian sure

Brian

15:23

@pH13 "Welcome back, to EXTREME QUANTUM CHEMISTRY!! Today, John is going to attempt QCISD/aug-cc quadruple zeta on a very challenging hypervalent system -- this promises to be tough. And.... he's off! Ok folks! Tune in about thirty-six hours from now and we'll. See. How. He. DID!"

2

pH13

@Brian fantastic

a seldom real world lol

Brian

15:41

Yeah. Probably closer to '36 days' is more like it.

Wildcat

15:56

Greetings, humans!

Reviewing an article written in Word was not as terrible as expected. :D

user116211

!!greet/@Wildcat

Wildcat

No greet for the cat?! :(

user116211

I'm missing @Chemobot

Wildcat

WHERE IS MY GREET?!

user116211

@Wildcat The bots are not here.

IͶΔ

15:59

NOT IN MAH POCKET I SWEAR

Wildcat

@MAFIA36790 that is questionable! Everyone who is there might be a bot! :O

user116211

@Wildcat You are an AI!

Wildcat

@IͶΔ is AI, I'm a cat.

IͶΔ

Nah, he's just a chemical in disguise

user116211

::Resistance is Futile::

Brian

16:21

My wife and I have come to the conclusion that I am Data.

pH13

@Wildcat o/

@Brian then it must be true

Brian

It's a good analogy -- there are certain things about human nature that most people just get, intuitively, that I ... don't.

Loong

@Brian "fully functional"?

pH13

my father-in-law behaves quite often very sheldon-ish

Brian

@Loong Our 5yo and 2.5yo boys say..... yes.

:-P

Loong

16:28

;-D

Brian

@pH13 I like to flatter myself by thinking I'm not quite that bad off.

(no offense to your father-in-law!)

But, e.g., I had to have explained to me why most people have a desire to "go out"

Loong

@Wildcat news.nationalgeographic.com/2016/04/…

2

pH13

@Loong oh no ... my adblocker is on

Loong

@pH13 oh no!

pH13

@Brian meh ... that doesn't make you unique ;D

make ... makes? ... the latter? it makes ... hmm

Brian

16:33

Oh, I'm not claiming uniqueness - just uncommonness.

<--- Not normal.

pH13

not normal when considering the mean of a normal distribution? ;)

Brian

Yeap, that one.

pH13

than nearly no one is *g*

Brian

But, then, probably no one who spends much time in here probably would count as normal.

:-)

Wildcat

@Loong :D

pH13

16:36

@Brian I wanted to say something like that. We all seem to like our online lifes and answering questions or whatever. We like to be at home, at offices, or on our smartphones reading SE stuff and chat online. Within our not so small subgroup of "all people" this is normal behaviour. So ... :)

stupid live - life thing ...

Brian

@pH13 Is okay, I used 'probably' twice in ~rapid succession there.

pH13

@Brian I changed my input to this:

! b3lyp def2-tzvp rijcosx def2-tzvp/j ecp{def2-tzvp,def2-tzvp/j} d3bj gcp(dft/tz)
! opt tightscf grid5 gridx5 cosmo(acetonitrile) pal8
%maxcore 1536
* xyz 0 1

and the error still appears

is the input case sensitive?

Brian

@pH13 No, AFAIK completely case-insensitive

pH13

I think I'll post it in the orca forum ...

Brian

@pH13 Agreed - it's either a bug, or there's something subtle missing from your input .

The entire geometry is somehow not being passed to the gCP tool, and the basis set passed is completely haywire.

mmm

wait

pH13

16:44

pH13 is waiting

Brian

I bet it's a bug.

pH13

please hold the line

Brian

hehe

pH13

I hope so ... I don't like questions were I didn't see obvious things and look like an idiot.

Wildcat

orcaforum.cec.mpg.de/viewtopic.php?f=11&t=1866

Don't you have the same problem?

Brian

16:47

Try replacing the entire ECP{...} with ECP{SD(28,MWB)}

No, it's calling the gCP tool fine, it's just that the parameters passed to it seem to be munged.

pH13

but gcp(dft/sv(p)) also does not work ... :D

Brian

(I haven't done much with ECPs, that may not be a valid input...)

pH13

that's why I use svp or tzvp ...

bugchucker will find a solution

Brian

It may be that the ECP{def2-TZVP} auto-substitution isn't passing the necessary information on to the gCP tool. Hopefully, explicitly specifying the Stuttgart-Dresden ECP to be used will make it happy.

Either way, you should probably still post to the forum. Either this works, and it's a bug in the ECP{def2-TZVP} style of syntax.... or it won't work, and hopefully they can fix it!

pH13

post has been done

pH13

17:04

probably I should have sticked with b3lyp/6-31g* and gaussian ;)

Data left :o

pH13

17:20

my first undownvote ... woohoo

where is my badge?

Ramanewbie

18:14

!!greet

Welcome to The Periodic Table et! Here are our chat guidelines and it's recommended that you read them. If you want to turn Mathjax on, make a bookmark of the link in this answer. Happy chatting!

pH13

@IͶΔ !!table

Ramanewbie

(╯°□°)╯︵ ɯsıɥdɹoɯouǝʞs

IͶΔ

@pH13 Sorry, out of service right now

pH13

!!table

Ramanewbie

(ﾉ｀△´)ﾉ~┻━┻

pH13

18:23

impossibru

Mithoron

Hi everyone

IͶΔ

\o

pH13

hello

IͶΔ

!!ice cream for @Mith

Ramanewbie

Mithoron

18:26

Haha :)

IͶΔ

18:58

@Mithoron How're you doing?

Haven't seen you a lot in chat lately.

Mithoron

19:10

@IͶΔ Well, there was Easter etc.

Hippalectryon

19:36

o/

Mithoron

@Hippalectryon o/

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