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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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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Why does chloromethane have a larger dipole moment than chloroform?
Why does $\ce{CH3Cl}$, methyl chloride, have a larger dipole moment than $\ce{CHCl3}$, chloroform?
Let us consider $\ce{C-Cl}$ bond moment to be $x$ and that of $\ce{C-H}$ bond to be $y$.
In $\...
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Is dipole moment a vector?
Isn't it a misconception to assume that dipole moments are similar to vectors in their behavior? My reasons are as follows:
Let us take an example: Methane ($\ce{CH4}$)
Clearly, the hydrogen atoms ...
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How to calculate molecular dipole moment from a known wavefunction?
Say I have a molecular wavefunction as a set of molecular orbitals and want to calculate the molecule's dipole moment, but don't know how! I searched a lot but couldn't find any practical example.
$$\...
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How to calculate transition dipole moment from two known wavefunctions
I am interested in calculating the transition dipole moment (TDM) from the information from two wavefunctions of different states. This is somewhat similar to calculating the molecular dipole moment ...
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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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Dipole Moment in P4O8 molecule
So from the structure, which seems to be quite symmetrical, according to me the dipole moment should be zero.
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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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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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Why don't polar and non-polar compounds dissolve each other?
Dipoles can also be induced in polar and non polar compounds, then why don't they dissolve?
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Is Hydrogen Bonding a Type of Dipole Dipole Interaction?
I understand that dipole dipole forces is due to the attraction of the different partials charges of atoms in different molecules due to their different electro-negativities.
For hydrogen bonding, ...
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Dipole Moment of Normal Water vs Heavy Water
The question is in the title itself.
My guess: Higher for Normal water.
My Reasoning: Internet told me Deuterium is more electronegative than Protium. So, there should be less difference between ...
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Does the distance increase as the polarity increases?
According to the dipole moment's definition, as polarity increases, the distance between the centres of positive and negative charges increases. In the ionic bond, as the polarity is maximum, the ...
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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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Link between centrosymmetry, dipole moment and chirality
What is the relationship between the three concepts in the title?
I know all centrosymmetric molecules are achiral, but not all achiral molecules are centrosymmetric. Thus, there are no molecules ...
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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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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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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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Non-zero dipole moment of hydroquinone
Why does hydroquinone possess a non-zero dipole moment? The $\ce{OH}$ groups present at para positions on the benzene ring should cancel the effect of each other... if there is a plane change then ...
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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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Is Hexafluorocyclohexane the "Most Polar" Small Molecule?
Earlier this year, there was a lot of attention when all-cis 1,2,3,4,5,6-hexafluorocyclohexane was synthesized*:
Notably, C&E News quoted the lead author:
This compound is remarkable for being ...
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Dipole moment and polarity of borazine / borazole / inorganic benzene
What is the dipole moment of borazine? I tried googling it but can't find a reliable source. I searched in JD Lee too. It might have it but I could not find.
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Using covalent or ionic radius when calculating dipole moment
When the ionic character of a bond is above 50% should I use ionic radius instead of covalent one when calculating the dipole moment?
The formula I have for dipole moment is $\mu = \text{(% ionic ...
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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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How to explain the periodic trends in boiling points in groups?
Observing the trend of boiling points of the compounds listed, choose the appropriate terms to fit into the blanks:
\begin{array}{lr}
\hline
\text{Compound} & \text{b.p.}/\pu{°C}\\
\hline
\ce{H2Te}...
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How are reactivity and dipole moment related?
Recently, I came across a question: which of the two compounds has a greater reactivity; $\ce{NH_{3}}$ or $\ce{NF_{3}}$?
It is known that despite the same structure the dipole moment of $\ce{NH_{3}}$...
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How to determine which of two similar compounds has the larger dipole moment?
I am solving some problems involving the order of dipole moments of some compounds. I could solve most of them but the following:
Which has greater dipole moment?
$\ce{CH3F}, \ce{CH_3Cl}$
Since ...
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How do I figure out the relative polarity of organic compounds?
It's a question on my quiz which I guessed right and couldn't do the reasoning:
Based on the intermolecular forces, predict the boiling points of the following substances and list them in the order ...
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What is the relationship between dipole moment and solubility?
I thought a large dipole moment meant the substance was polar, so I'm confused by the following statement (from Wikipedia) that "With a dipole moment of 3.92 D, acetonitrile dissolves a wide range of ...
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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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Relationship between electric dipole moment and polarization?
$$\vec{p}_\text{ind} = \alpha \vec{E}$$
The induced dipole moment is the polarizability times the electric field vector.
$$\vec{P}(\omega) \propto \chi^{(1)}(\omega) \vec{E}(\omega)$$
The polarization ...
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Order of dipole moments
What is the order of dipole moments for $\ce{SO3, SiO2, P2O5,}$ and $\ce{Cl2O7}$? This question is from a book and the answer given is $\ce{Cl2O7 < SO3 < P2O5 < SiO2}$. Can someone explain ...
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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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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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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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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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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 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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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) ...