James McGinn
2019-06-01 20:26:05 UTC
OK, with those provisos out of the way, let’s begin.
I have omitted Robin's "privisos" because they are just politics, not science. I you are interested in these provisos and the conversation that led up to this post, here is a link. Read the comment stream:
RB:
1. Coloumb’s Law.
Mr McGinn invokes Coloumb’s law in this video, saying something along the lines that it should be attractive at all distance when molecules of water move close to each other.
JMcG:
Note that Robin did not quote me directly. The tendency to paraphrase one's intellectual opponent is a clever way to misrepresent what they actually stated/intended.
As is well understood, Coulomb's law is applicable to the distance between the outer perimeter of atoms. The outer perimeter is delineated by their respective electron clouds.
By way of glossing over details and pandering to the ignorance and gullibility of the public, Robin is pretending that I indicated electron cloud overlapping--which would require "temperatures greater than the heat of the sun."
RB:
This is not correct.
JMcG:
Yes. I know it is incorrect, which is why I never stated any such thing, you lying piece of shit.
RB:
As any molecules (including water) move closer, there are attractive intermolecular forces between them, such as van der Walls, interactions, dipole-dipole interactions and, as we’ll see later, in some cases hydrogen bonding interactions. These favourable interactions all increase until a certain inter-molecular separation, beyond which, it becomes unfavourable for the molecules to get closer, this is due to short-range coloumbic repulsion by the molecules’ electron clouds. This is described by what is known as the Lennard-Jones potential. I won’t go into detail here, but you can easily look this up. Mr McGinn had not heard of this, and when it was pointed out to him described it as a deliberate attempt at obfuscation. Ermm, no, it’s called a measurable, real thing. Don’t take my word for it. Look up the Lennard-Jones potential on Wikipedia. Expect some vitriolic rebuttals at this point and make of them what you will.
JMcG:
LOL. The only tactic you got involves reestablishing the obscurity that initially allowed you to pretend you understand what you obviously don't.
RB:
2.Hydrogen bonding.
Mr McGinn has decided that the entire scientific community does not get hydrogen bonding.
JMcG:
Yes. As described here:
http://youtu.be/RfNuWJDJvRw
RB:
On the contrary, hydrogen bonding is extremely well understood.
JMcG:
Your desperate attempt to misrepresent my words suggests otherwise.
RB:
A hydrogen bond is the interaction of a hydrogen atom on an electronegative element with the lone pair of electrons on an adjacent electronegative element. In the case of water, the electronegative element is oxygen, and each oxygen atom has two covalently bonded hydrogens and two lone pairs. Each oxygen can hydrogen bond to up to two other hydrogens. Nothing controversial so far.
JMcG:
I agree. But there is nothing specific here either. You are glossing over the trivia that is not controversial.
RB:
We can measure all of the internuclear distances, using a variety of techniques (McGinn will deny this is possible, he is talking shite, this has been shown many, many, many times, using many different techniques). We know that in liquid at its most dense (4 degrees C), i.e. when it will have the shortest intermolecular separation, the average separation between one oxygen atom and an adjacent oxygen atom is about 2.82 Å. We know that the covalent bond length of the O-H bond of a water molecule is 0.96 Å and that average hydrogen bonding distance between the hydrogen on one water molecule an adjacent oxygen 1.88 Å. These aren’t guesses (Mr McGinn would have you believe differently) these have been measured time and time again using a wide variety of different techniques, all of which give consistent results.
JMcG:
Right. There is a distance between water molecules in liquid water that is inconsistent with what is seen in other molecules AS PER COULOMB'S LAW.
RB:
Mr McGinn has decided that hydrogen bonding can be invoked to ‘remove’ the dipole moment of liquid water.
JMcG:
Well, yes. (And in no way shape or form did I ever imply that this involved or required the overlap of electron clouds. As Robin is dishonestly implying.) What I am saying is that Linus Pauling made an error when he assumed that the geometric structure of molecules dictates the dipole AND that since this geometric structure is essentially permanent (at the ambient temperature where H bonding occurs) that, therefore, the H2O molecule's dipole is fixed/static/permanent.
It is not the geometric structure that dictates H2O's dipole, it is the electrical gradient that is associated with the molecule's structure that is causal. And that is important because geometric structure can't be counteracted or neutralized. In sharp contrast, electrical gradient can be counteracted or neutralized.
Pauling made an error--and everybody followed.
The 'anomalies' of H2O exist because theory has incorporated the false assumption that H2O polarity is static/fixed/constant when in reality it is highly variable.
Paling's Omission:
RB:
He proposes that liquid water ‘stacks’ in a tetrahedral form, which they sort of do, on average, and that the hydrogen bonds between one water molecule’s oxygen atom and hydrogen atoms on adjacent water molecules gets short enough that the dipole cancels out. It is this latter part that is what we in the chemistry community call bullshit. In order to be able to cancel the dipole moment, the hydrogen bond lengths would need to be the same as the covalent bond lengths. McGinn cheerfully agreed with this pint in one of his patronising replies (“now your getting it”, or words to that effect).
JMcG:
Well, possibly I am not fully informed on the details of covalent bonding. If you are saying that covalent bonding involves electron cloud overlap (I am assuming it doesn't) then technically what you are saying is correct and I am wrong on this point. But your point is tangential to my point and therefore you are just being dogmatic.
And so, I concede that I may be uninformed about the true nature of covalent bonding. So, your assertions about DFT are irrelevant because for them to be relevant there would have to be electron cloud overlap, which I never intended to suggest/indicate.
RB:
For fun, I did a quantum calculation using the density functional theory (DFT) approach. Mr McGinn was not happy about this. He stated that I was making assumptions about the electron density in the hydrogen bonds. Nope. DFT does not make this assumption,
JMcG:
I didn't say it did. I said you made the assumption by way of analogy to covalent bonding which I never intended.
it calculates the electron density (clue’s in the name) for any given coordinate system of atoms. You give it the distances, it will give you a model of the electron density and an energy of the system. In this model, I had two hydrogens atoms of distinct water molecules hydrogen-bonded to the two lone pairs of a third water molecule:
H H H H
\ / \ /
O O
. .
. .
H H
\ /
O
(apologies for the terrible representation – typed rather than drawn!). Here the solid lines indicate the covalent bonds, the dotted lines the hydrogen bonds. So far, so exactly like the standard (real) description.
JMcG:
Right.
RB:
I first optimised the equilibrium geometry (for the purists: M06-X2 functional, aug-CC-pDVZ basis set, C-PCM solvent model, solvent = water) of this simple structure and this gave an average hydrogen bond O…H length of 1.89 Å and an O…O separation of about 2.85 Å. Compare this with the observed average values of 1.88 Å and 2.82 Å in liquid water (which have been measured many, many times).
JMcG:
Right. There is a calculated (not directly observed) AVERAGE distance between H2O molecules in liquid H2O. This "unexplained" distance will change with temperature differences, but not that much. (Note: I put the word unexplained in quotes because my theory actually does explain it whereas the standard model fails.)
RB:
That is an error of 1% or less for the bond metrics of this simple model compared with the measured values for liquid water. We can reasonably confidently take the energy of this model as a ‘zero point’ standard value (electronic energy = -229.265956 hartrees) with which to compare the results returned by Mr Denks theory.
JMcG:
Convoluted.
RB:
I then moved the water molecules closer so that the hydrogen bond distance was the same as the covalent bond length (0.96 Å), as would be necessary in order for the dipole moment to cancel out – the central tenet of mr Denk’s, I’m sorry, Mr McGinn’s “theory” and reran the calculation.
JMcG:
You've stated nothing about the origin of the dipole moment. Do you dispute what I've stated above about the difference between it being a consequence of molecular geometric assymetry and it being a consequence of electrical gradients? You need to be clear on this point.
I have to admit, Robin, now that I've read this carefully you don't seem as dumb as it once seemed.
James McGinn / Solving Tornadoes
I have omitted Robin's "privisos" because they are just politics, not science. I you are interested in these provisos and the conversation that led up to this post, here is a link. Read the comment stream:
RB:
1. Coloumb’s Law.
Mr McGinn invokes Coloumb’s law in this video, saying something along the lines that it should be attractive at all distance when molecules of water move close to each other.
JMcG:
Note that Robin did not quote me directly. The tendency to paraphrase one's intellectual opponent is a clever way to misrepresent what they actually stated/intended.
As is well understood, Coulomb's law is applicable to the distance between the outer perimeter of atoms. The outer perimeter is delineated by their respective electron clouds.
By way of glossing over details and pandering to the ignorance and gullibility of the public, Robin is pretending that I indicated electron cloud overlapping--which would require "temperatures greater than the heat of the sun."
RB:
This is not correct.
JMcG:
Yes. I know it is incorrect, which is why I never stated any such thing, you lying piece of shit.
RB:
As any molecules (including water) move closer, there are attractive intermolecular forces between them, such as van der Walls, interactions, dipole-dipole interactions and, as we’ll see later, in some cases hydrogen bonding interactions. These favourable interactions all increase until a certain inter-molecular separation, beyond which, it becomes unfavourable for the molecules to get closer, this is due to short-range coloumbic repulsion by the molecules’ electron clouds. This is described by what is known as the Lennard-Jones potential. I won’t go into detail here, but you can easily look this up. Mr McGinn had not heard of this, and when it was pointed out to him described it as a deliberate attempt at obfuscation. Ermm, no, it’s called a measurable, real thing. Don’t take my word for it. Look up the Lennard-Jones potential on Wikipedia. Expect some vitriolic rebuttals at this point and make of them what you will.
JMcG:
LOL. The only tactic you got involves reestablishing the obscurity that initially allowed you to pretend you understand what you obviously don't.
RB:
2.Hydrogen bonding.
Mr McGinn has decided that the entire scientific community does not get hydrogen bonding.
JMcG:
Yes. As described here:
http://youtu.be/RfNuWJDJvRw
RB:
On the contrary, hydrogen bonding is extremely well understood.
JMcG:
Your desperate attempt to misrepresent my words suggests otherwise.
RB:
A hydrogen bond is the interaction of a hydrogen atom on an electronegative element with the lone pair of electrons on an adjacent electronegative element. In the case of water, the electronegative element is oxygen, and each oxygen atom has two covalently bonded hydrogens and two lone pairs. Each oxygen can hydrogen bond to up to two other hydrogens. Nothing controversial so far.
JMcG:
I agree. But there is nothing specific here either. You are glossing over the trivia that is not controversial.
RB:
We can measure all of the internuclear distances, using a variety of techniques (McGinn will deny this is possible, he is talking shite, this has been shown many, many, many times, using many different techniques). We know that in liquid at its most dense (4 degrees C), i.e. when it will have the shortest intermolecular separation, the average separation between one oxygen atom and an adjacent oxygen atom is about 2.82 Å. We know that the covalent bond length of the O-H bond of a water molecule is 0.96 Å and that average hydrogen bonding distance between the hydrogen on one water molecule an adjacent oxygen 1.88 Å. These aren’t guesses (Mr McGinn would have you believe differently) these have been measured time and time again using a wide variety of different techniques, all of which give consistent results.
JMcG:
Right. There is a distance between water molecules in liquid water that is inconsistent with what is seen in other molecules AS PER COULOMB'S LAW.
RB:
Mr McGinn has decided that hydrogen bonding can be invoked to ‘remove’ the dipole moment of liquid water.
JMcG:
Well, yes. (And in no way shape or form did I ever imply that this involved or required the overlap of electron clouds. As Robin is dishonestly implying.) What I am saying is that Linus Pauling made an error when he assumed that the geometric structure of molecules dictates the dipole AND that since this geometric structure is essentially permanent (at the ambient temperature where H bonding occurs) that, therefore, the H2O molecule's dipole is fixed/static/permanent.
It is not the geometric structure that dictates H2O's dipole, it is the electrical gradient that is associated with the molecule's structure that is causal. And that is important because geometric structure can't be counteracted or neutralized. In sharp contrast, electrical gradient can be counteracted or neutralized.
Pauling made an error--and everybody followed.
The 'anomalies' of H2O exist because theory has incorporated the false assumption that H2O polarity is static/fixed/constant when in reality it is highly variable.
Paling's Omission:
RB:
He proposes that liquid water ‘stacks’ in a tetrahedral form, which they sort of do, on average, and that the hydrogen bonds between one water molecule’s oxygen atom and hydrogen atoms on adjacent water molecules gets short enough that the dipole cancels out. It is this latter part that is what we in the chemistry community call bullshit. In order to be able to cancel the dipole moment, the hydrogen bond lengths would need to be the same as the covalent bond lengths. McGinn cheerfully agreed with this pint in one of his patronising replies (“now your getting it”, or words to that effect).
JMcG:
Well, possibly I am not fully informed on the details of covalent bonding. If you are saying that covalent bonding involves electron cloud overlap (I am assuming it doesn't) then technically what you are saying is correct and I am wrong on this point. But your point is tangential to my point and therefore you are just being dogmatic.
And so, I concede that I may be uninformed about the true nature of covalent bonding. So, your assertions about DFT are irrelevant because for them to be relevant there would have to be electron cloud overlap, which I never intended to suggest/indicate.
RB:
For fun, I did a quantum calculation using the density functional theory (DFT) approach. Mr McGinn was not happy about this. He stated that I was making assumptions about the electron density in the hydrogen bonds. Nope. DFT does not make this assumption,
JMcG:
I didn't say it did. I said you made the assumption by way of analogy to covalent bonding which I never intended.
it calculates the electron density (clue’s in the name) for any given coordinate system of atoms. You give it the distances, it will give you a model of the electron density and an energy of the system. In this model, I had two hydrogens atoms of distinct water molecules hydrogen-bonded to the two lone pairs of a third water molecule:
H H H H
\ / \ /
O O
. .
. .
H H
\ /
O
(apologies for the terrible representation – typed rather than drawn!). Here the solid lines indicate the covalent bonds, the dotted lines the hydrogen bonds. So far, so exactly like the standard (real) description.
JMcG:
Right.
RB:
I first optimised the equilibrium geometry (for the purists: M06-X2 functional, aug-CC-pDVZ basis set, C-PCM solvent model, solvent = water) of this simple structure and this gave an average hydrogen bond O…H length of 1.89 Å and an O…O separation of about 2.85 Å. Compare this with the observed average values of 1.88 Å and 2.82 Å in liquid water (which have been measured many, many times).
JMcG:
Right. There is a calculated (not directly observed) AVERAGE distance between H2O molecules in liquid H2O. This "unexplained" distance will change with temperature differences, but not that much. (Note: I put the word unexplained in quotes because my theory actually does explain it whereas the standard model fails.)
RB:
That is an error of 1% or less for the bond metrics of this simple model compared with the measured values for liquid water. We can reasonably confidently take the energy of this model as a ‘zero point’ standard value (electronic energy = -229.265956 hartrees) with which to compare the results returned by Mr Denks theory.
JMcG:
Convoluted.
RB:
I then moved the water molecules closer so that the hydrogen bond distance was the same as the covalent bond length (0.96 Å), as would be necessary in order for the dipole moment to cancel out – the central tenet of mr Denk’s, I’m sorry, Mr McGinn’s “theory” and reran the calculation.
JMcG:
You've stated nothing about the origin of the dipole moment. Do you dispute what I've stated above about the difference between it being a consequence of molecular geometric assymetry and it being a consequence of electrical gradients? You need to be clear on this point.
I have to admit, Robin, now that I've read this carefully you don't seem as dumb as it once seemed.
James McGinn / Solving Tornadoes