The Periodic Table

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hBy2Py

17:14

@DHMO Bear in mind, these charges have little to do with the dipole.

DHMO

@hBy2Py why?

hBy2Py

An appreciable fraction of the electron density on the carbon side of the bond plane is associated with the oxygen atom.

It's due to the way AIM defines the atom boundaries

For CO, the ORCA computation puts the dipole at 0.128 Debye, oxygen positive

DHMO

for HCO?

hBy2Py

For HCO+, it puts it at 4.04 Debye, oxygen negative

DHMO

that's a large dipole

hBy2Py

17:20

For sure

Protonation has a remarkably significant effect on the electron density distribution.

The proton basically acts as a localization center, IIUC

In the case of HCO+, it appears that it localizes electrons away from itself.

Related -- with CO, often it's written as a triple bond

But the AIM ELF basin populations don't support that:
C LP - 2.49e (Slightly over one lone pair on C)
C-O bond - 3.07e (~1.5-order bond)
O LPs - 4.23e (~two lone pairs)

Again, that C-O bond in CO looks to have appreciable charge-shift bond character. High-level, that means that electron density gets "smooshed" out from the bonding region and (often) into the lone-pair region of the atoms involved.

Much of the smooshed density appears to end up on carbon, with a tad going onto the oxygen.

DHMO

so what is the conclusion? @hBy2Py

hBy2Py

CO has a double bond with charge shift character

HCO+ is likely protonated CO, also with a C=O double bond, with some charge shift character but overall less than with CO

Protonation of CO appears to change the direction of the dipole moment rather dramatically

@DHMO Not sure if there's any particular connection back to the mass spectrum of formic acid

DHMO

17:35

is it particularly stable?

hBy2Py

¯\_(ツ)_/¯

I can't tell that from the quick analyses I've done thus far.

1 hour later…

M.A.R.

18:37

@paracresol I will deflect the nukes with my coolness

M.A.R.

18:48

!!flip/Be Nice

Chemobot

( つ•̀ω•́)つᗺǝ Nᴉɔǝ

Jan

@Loong There’s a connection between Word and typography?

M.A.R.

@Jan Yes.

Loong

Is that supposed to be a rhetorical question?

M.A.R.

The amount of time you spend typing a document in Word is inversely proportional to your typography skills powered by 1/4.

Jan

18:52

@hBy2Py Well, you can synthesise carbon monoxide by adding sulphuric acid to formic acid; the mechanism is probably protonation, loss of H2O and then loss of the H-C proton. So there’s no reason why it wouldn’t happen in MS.

It’s supposed to be a joke question ^^ @M.A.R. picked it up well ^^

Loong

@M.A.R. Actually, people without such skills can be very fast. However, the results speak for themselves.

M.A.R.

And an echo question grammatically

@Loong Fast is usually of poor quality

Unless it's a formula one race.

Loong

heh

2 hours later…

orthocresol

20:29

I'm nowhere near an expert on this but my best guess is that the diene coordinates to Pd. The OH attacks the diene generating a Pd-allyl species and then chloride attacks (first step similar to the Wagner oxidation, last step similar to a Trost allylation). — orthocresol ♦ 7 hours ago

9 upvotes?? really...?

I guess that means I'm probably correct..

2 hours later…

Jan

22:38

Epic day number 33~ \o/

@ortho I wonder why your post didn’t get any upvote other than mine yet ô.o

Loong

23:00

@Jan because he cannot count to three ;-)

Jan

@Loong You know that there are three kinds of people? ;)

DHMO

23:40

@orthocresol do you think 9 knowledgeable people came over and upvoted your comment?

they just think it's plausible

@Loong could you do MO-calculations of t-BuH?

Loong

@DHMO no, not really

DHMO

@hBy2Py the above

ok thanks @Loooooong

@Loong what about MeCl?

i'm probably more interested in MeI though

or MeO-Na+

orthocresol

@Loong Oops...

trying to think of a HL3 joke

Jan

@orthocresol Half-Life 3 confirmed? =O

orthocresol

23:56

Personally I'm waiting for Portal 3 although I suspect they aren't working on it :(

Jan

Still trying to think of a witty quote to slap between acknowledgements and introduction. I don’t like the fact that they are left page–right page. But maybe I should just leave an intentionally blank page?

Loong

@Jan I quoted Marie Curie. That was an easy choice in my case.