Questions tagged [dipole]
For questions about the dipole moment of a bond or a molecule; its calculation, comparison with other bonds or molecules, affect on molecular properties, etc.
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SO2 vs SO2F2 Dipole Moment
Which molecules has the largest overall dipole moment between $\ce{SO2}$ and $\ce{SO2F2}$?
$\ce{SO2}$ is bent and therefore polar while $\ce{SO2F2}$ is a tetrahedral but the strong $\ce{S-F}$ bonds in ...
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Order of Polarities/Dipole Moments of CH3F, CH3Cl, CH3Br and CH3I [duplicate]
While explaining how to decide polarities/dipole moments of molecules, my teacher highlighted an exception to the statement:
For similar compounds like hydrides formed by different elements of a ...
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Are van der Waals forces the same thing as intermolecular forces? [duplicate]
Like the name suggests, intermolecular forces are those between molecules and can be forces of attraction between permanent dipoles or temporary dipoles. However, it seems that the definition of van ...
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Dipole-dipole vs London dispersion forces for deducing melting and boiling points
To determine the melting and boiling points of compounds, London dispersion forces are typically compared. However, why are the polarity and dipole-dipole forces ignored?
For instance, $\ce{HI}$ has a ...
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Which one has a greater dipole moment: benzamide or benzoic acid?
My guess is that, since the relative electronegativities are similar, therefore the difference would arise only due to magnitudes of difference in electronegativities. And hence the strength should be ...
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Why does AsH3 have a higher boiling point than HBr?
Aside from the general trend of the boiling points of the hydrides, I noticed how the group 15 hydrides somehow "overtook" the group 17 ones in boiling point, which felt weird.
Notably, H-...
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Why would the chlorine atom be assigned a positive partial charge in chloroform and carbon tetrachloride?
Looking at electronegativity tables, chlorine consistently has a higher electronegativity than carbon. However, when I use simple algorithms (molcalc, acc2), I get a positive partial charge on the ...
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Dipole Moment in P4O8 molecule
So from the structure, which seems to be quite symmetrical, according to me the dipole moment should be zero.
user136760
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Does an ionic bond have a dipole?
Is an ionic compound like NaCl considered a dipole? It has a positive side (Na+) and a negative side (Cl-). Or is it true that an ionic bond does not have a dipole because a dipole is, by definition, ...
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Dipole moments of trans and cis nitrous acid
I have a paper due about the isomers of nitrous acid, using various calculations methods to find molecular properties like their dipole moment. I've found the dipole moment of trans isomer to be 1.987 ...
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Polyatomic molecule vibrational spectra - Molecular dipole expansion in Taylor series
To give some context: I am studying the molecular spectra in the context of an introductory course to atomic and molecular physics. My professor is using the transition rate expression from an initial ...
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Why is the dipole moment of Anisole less than that of Phenol? [closed]
According to Wikidata, anisole has a dipole moment of 1.38D and according to this page on Researchgate, phenol has a dipole moment of 1.70D.
Resonance in anisole:
Resonance in phenol:
According to my ...
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Why is the inductive effect possible?
Firstly, I must preface that I am a Biology student. To elaborate my question, I was looking for the reason why carboxylic acids are more acidic than alcohols, despite both compounds containing —OH ...
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Can the charges at the ends of a dipole in a polar molecule exceed unit electronic charge?
According to my current understanding, charges at the end of the dipole of a polar molecule are formed due to the shifting of the electron cloud towards the more electronegative atom.
In my book it is ...
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Best description of forces/ mechanisms that stabilize the interaction between a hydrophobic protein binding pocket and a hydrophobic ligand
This is a more theoretical or definition question that is related to the terms "hydrophobic effect", "hydrophilic interaction", and "van der Waals' forces" (and others I ...
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Can we find dipole moment of water from a familiar property?
There are many videos on Youtube showing deflection of a stream of water by a charged rod. My question is whether we can do a rough calculation of the dipole moment of water molecules using this ...
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Comparing dipole moments of hydrogen halides
How can we compare dipole moments of halide ions?
As we go down the group, the induced charged hydrogen decreases as electronegativity difference between hydrogen and corresponding halogen decreases ...
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How to convert from dipole derivative to atomic units?
I need to convert dipole derivative output by Gaussian into atomic units. The dipole derivative is given in Gaussian in the weird units $(\mathrm{km/mol})^{1/2}$. I know that
$\pu{1 D^2/(Å^2amu)}$ = $\...
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Should there be a better explanation on Van Der Waals force? [duplicate]
The explanation on how Van der Waals force forms is this: Van der Waals forces consist of induced, temporary dipoles between neighbouring molecules. These are caused by constantly shifting electron ...
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What does Partial charge means in Dipole Dipole forces [duplicate]
Dipole-dipole forces act between the molecules possessing permanent dipole. Ends of the dipoles possess “partial charges” and these charges are shown by Greek letter delta (δ). Partial charges are ...
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Are spontaneous/induced dipoles the same as van der Waals forces?
I am puzzled by the names of dipoles.
What is the difference among permanent dipoles, spontaneous dipoles, van der Waals forces, and intermolecular forces?
Does "The intermolecular force" ...
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Quantitatively Calculate Dipole Moment [duplicate]
Recently, I have been reading up on articles relating to the dipole moments of different molecules (specifically this). I see how they can get bond lengths and experimental dipole moments with ...
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Differences between formulae for dipole–dipole interaction energy
I came across two formulae for dipole-dipole interaction energies on Chemistry LibreTexts — Dipole-Dipole Interactions:
$$V=-\frac{2\mu_1 \mu_2}{4\pi\epsilon_0r^3}\tag{3}$$
and
$$V=-\frac{2\mu^2_\...
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Why is the intensity of the IR spectra of IBr higher than that of ICl?
Why is the intensity of the IR spectra of $\ce{IBr}$ higher than that of $\ce{ICl}$?
I know that the IR spectra intensities are proportional to the derivative of the dipole moment with internuclear ...
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Dielectric polarization: how to identify what part of the total polarization (dipolar+electronic+ionic) I need (conceptual question, I use DFPT, VASP)
I am doing polarization calculations to get data for use in other calculations. To start with, I want to calculate the static dielectric constant. However, I'm a newbie to polarization and it is a ...
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TD-DFT transition dipole moment vector does not align with experimental data
I have been modelling excited states of some molecules with similar stucture using TD-DFT theory, however, I have encountered an issue that sometimes transition dipole moment does not align with the ...
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What is the direction of the net electric dipole moment in hydronium H3O+?
Assuming electric dipole moment points towards the negative charge, what would its direction be in hydronium?
Although the bonding electron density is distorted towards the more electronegative oxygen,...
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Net direction of dipole moment in oxygen difluoride
What is the net direction of dipole moment in $\ce{F2O}$ molecule?
In the case of $\ce{NH3}$ and $\ce{NF3}$ molecules both have net dipole moment with direction reversed due to strong ...
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When do lone pairs affect dipole moments?
My textbook says that NH3 has more dipole moment than NF3 despite F being more electronegative than H, because the dipole moment due to the lone pair on N points in the same direction as the ones due ...
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Why hydrogen bonds are stronger than Van der Waals forces?
Why the hydrogen bonds are more intense than Van der Waals forces in the case where the molecules with the Van der Waals forces have a stronger dipolar moment than the molecules with the hydrogen bond?...
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Why do molecules showing a pure rotational spectra require a permanent dipole?
I understand that pure rotational spectra only exist for molecules which have a permanent dipole moment. The common explanation is "so that they can interact with the E-field of the incoming ...
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How is dipole moment of ammonia less than sulphur dioxide? [closed]
Sulphur dioxide has only two bonds at 180º so shouldn't the dipole moment of molecule be 0 and as ammonia has 1 lone pair so it's dipole can't be 0 so how Sulphur dioxide has more dipole moment than ...
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How does this rotation minimize the dipole moment?
A paper I'm reading says:
The low energy conformation of 3 minimizes the overall dipole moment of the compound and thus rotates the exocyclic amide 180° from desired conformation, as can been seen in ...
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Why does ozone have a dipole moment different than 0 [duplicate]
First of all, I know that the reason for this is the bent structure of the molecule.
However, we were taught in my class that the dipole moment of a molecule is equal to the vector sum of the dipole ...
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Dipole moment of (1s,2s,3s)-1,2,3-trichlorocyclopropane
Which of the following compounds has a zero dipole moment?
Only one of the options is correct
According to me, it looks like both options (c) and (d) are right. Since the dipole moments of option (c) ...
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Estimation of dipole moments in aromatic compounds
If it asks to compare dipole moment in aromatic compounds then do we see inductive or resonance effects or do we see a mix of both?
E.g. we have to compare dipole moment in pyrrole and furan then in ...
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Relative strength of intermolecular forces [duplicate]
My attempt at a solution:
First I look for hydrogen bonds:
The only compounds with hydrogen bonds are the second and fourth ones, so they have the strongest intermolecular forces. The second must have ...
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Dipole moments of cis and gem alkenes [duplicate]
The procedure for comparing dipole moments for cis- and trans-alkenes is quite easy, but how to compare dipole moments of
1,1 dichloroethene (1); and
cis-dichloroethene (2)?
My teacher told me that ...
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Factors dominating forces between acetone and chloroform
What type of interaction is present between acetone and chloroform?
According to me, acetone has weak hydrogen-bonds with chloroform, the hydrogen on an electronegative atom has electron density that ...
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Why HBr has stronger attraction between molecules than CH3NH2?
Which of the following compounds exhibits dipole-dipole forces as its strongest attraction between molecules?
a) $\ce{CO2}$
b) $\ce{CH3NH2}$
c) $\ce{Kr}$
d) $\ce{H2}$
e) $\ce{HBr}$
From what I ...
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Why is CH4 Nonpolar but CH2Cl2 is polar?
I keep reading that the reason why $\ce{CH2Cl2}$ is polar because due to its tetrahedral shape, the dipoles can not cancel each other out but doesn't $\ce{CH4}$ also have tetrahedral shape too? I ...
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What is the link between the classical and quantum definition of the symmetry number?
From what I understand, the symmetry number for a molecule can be defined in 2 ways:
1. The quantum mechanical symmetry number corrects for overcounting the number of possible rotational states of a ...
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Why does 1,4-diiodobenzene have a non-zero dipole moment?
From this answer, I came to know that 1,4-diiodobenzene has a dipole moment of $0.19~\rm D$ in benzene at $20\ ^\circ\rm C$. On the basis of symmetry, I'd expect the bond moments due to the difference ...
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Dipole Moment of p-dibromobenzene
What is the dipole moment of p-dibromobenzene?
I know that p-dichlorobenzene has zero dipole moment, but my teacher said that this is not the case for bromine. I am still confused and feel its dipole ...
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The meaning of permanent dipole moment
I was asked in one question that which of all given molecules have a permanent dipole moment?
And $\ce{XeF6}$ was given as a correct answer quoting that it is a distorted octahedral, and hence the ...
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How do you explain partial charges in molecules that have a dipole? [closed]
For example if i have hydrogen and fluorine covalently bonded with each other, it would result in a polar molecule with the valence electrons being pulled closer to the fluorine than it is to the ...
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Raman scattering and "electron and proton center" of molecule
I am currently studying the textbook Infrared and Raman Spectroscopy, 2nd edition, by Peter Larkin. In a section entitled The Raman Scattering Process, the author says the following:
Light scattering ...
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Which has greater dipole moment: cis-1,2-dichloroethylene or 1,1-dichloroethylene?
Which has greater dipole moment: cis-1,2-dichloroethylene or 1,1-dichloroethylene?
I know that dipole moment depends upon the strength of dipole and angle between the dipoles.
1,1-Dichloroethylene ...
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Why is the net dipole moment of carbon dioxide equals zero [closed]
Why is the net dipole moment of carbon dioxide equal to zero? And what is the partial charge of carbon in co2? Is it +2 because it forms two polar bonds or if they cancel the effect of each other due ...
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Different direction of dipole moment in physics and chemistry [duplicate]
In chemistry, we learn that dipole moment tells us about measure of polarity in a molecule. In books, it is written that "conventionlly the direction of dipole moment is from electropositive to ...
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