75
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Why is it wrong to use the concept of hybridization for transition metal complexes?
Tetrahedral complexes
Let's consider, for example, a tetrahedral $\ce{Ni(II)}$ complex ($\mathrm{d^8}$), like $\ce{[NiCl4]^2-}$. According to hybridisation theory, the central nickel ion has $\mathrm{...
- 70.1k
52
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Why do compounds like SF6 and SF4 exist but SH6 and SH4 don't?
TL;DR Fluorine is electronegative and can support the extra negative charge that is dispersed on the six X atoms in $\ce{SX6}$, whereas hydrogen cannot.
First, let's debunk a commonly taught myth, ...
- 70.1k
46
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Are the lone pairs in water equivalent?
Water, as simple as it might appear, has quite a few extraordinary things to offer. Most does not seem to be as it appears.
Before diving deeper, a few cautionary words about hybridisation. ...
- 43.5k
27
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Relative acidities of alkanes, alkenes, and alkynes
You're right in that bond length, and therefore bond strength does affect acidity (see: $\ce{H2S}$, $\mathrm{p}K_\mathrm{a} = 7$ and $\ce{H2O}$, $\mathrm{p}K_\mathrm{a} = 15.7$). If we defined acidity ...
- 70.1k
20
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Why does bond angle decrease in the order H2O, H2S, H2Se?
The question asks why water has a larger angle than other hydrides of the form $\ce{XH2}$ in particular $\ce{H2S}$ and $\ce{H2Se}$. There have been other similar questions, so an attempt at a general ...
- 28.6k
20
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Sp5 hybridization in cyclopropane?
Until this post, $\mathrm{sp^1,~sp^2~\text{and}~sp^3}$ meant for me, that the hybrid orbitals would consist from one s orbital and one, two or three p orbitals. I thought of it being so, as this seems ...
20
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Does nitrogen inversion affect the basicity of amines?
Background
Amine basicity correlates with, among other things, the hybridization of the nitrogen orbital that is holding the lone pair of electrons. The less s-character in this orbital, the more ...
- 83.7k
20
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Hybridization of nitrogen in trisilylamine, (SiH3)3N?
Ordinarily and according to Bent’s rule, we would expect nitrogen’s lone pair to be in an $\mathrm s$ orbital and nitrogen using its three $\mathrm p$ orbitals to form three bonds to the three silicon ...
- 66.4k
19
votes
What is the hybridization of the carbonyl oxygen in a carboxylic acid?
I already pointed it out in the comments, but I believe it is time to give it some more thought and explanation. Let's deal with some conceptual issues first.
Hybridisation is a model, that can be ...
- 43.5k
19
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How to rationalise the planar structre of I2Cl6?
The bonding situation in the compound $\ce{(ICl3)2}$ is by far more complex than what is depicted in this book. The molecule itself has very high symmetry, i.e. $D_\mathrm{2h}$, that needs to be ...
- 43.5k
19
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Hybridisation of ClO2
I actually take issue with the question (which was asked of you not by you), as I think this oversimplifies a molecule, that still isn't well understood in the first place.
That is why I find this ...
- 43.5k
18
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Is nitrogen of aniline sp² or sp³ hybridized?
The nitrogen in aniline is somewhere between $\mathrm{sp^3}$ and $\mathrm{sp^2}$ hybridized, probably closer to the $\mathrm{sp^2}$ side. We are correctly taught that the nitrogen in simple aliphatic ...
- 83.7k
18
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What does it mean when it is said that an sp³ orbital has 25% s character?
Hybridisation is a purely mathematical concept, which makes it possible to explain experimentally found structures. The most prominent example for this is methane, where you can consider the central ...
- 43.5k
18
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What is Drago's rule? Does it really exist?
Going through what you posted, I think ‘Drago’s rule’ (which I never encountered, either at school or at university) gives good predictions but uses a largely terrible set of arguments.
For any atomic ...
- 66.4k
18
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Hybridization of nitrogen in trisilylamine, (SiH3)3N?
To test Jan's argument, I did an NBO analysis of your structure (optimized at PBE-D3/def2-SVP with NWChem 6.6 using a conformational search with MMFF94s and Avogadro as the starting point; a frequency ...
- 2,853
17
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Does s stand for sigma bond and p for pi bond?
You got it backwards.
The $\mathrm{s}$, $\mathrm{p}$, $\mathrm{d}$, $\mathrm{f}$ orbitals stand for sharp, principal, diffuse, and fundamental. Wikipedia: Electron Configuration § Notation:
The ...
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17
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Shape of sp³ hybrid orbital
Don't put too much trust in the absolute signs of wavefunction, for they all are arbitrary anyway. Look at it this way: an s orbital has one sign (*). One lobe of p orbital has the same sign, so when ...
- 30.7k
16
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How can the Bonding in IF7 be explained using LCAO method?
No 6-centre-10-electron bond.
The bonding situation in $\ce{IF7}$ is explained by Christe et. al. (see ssavec's answer) as a 6-centre-10-electron bond. In the article itself I found no real ...
- 43.5k
15
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Why can there not be more than one sigma bond in a set of bonds?
Why can there not be more than one sigma bond in a set of bonds?
There can be, even in simple carbon compounds. Bent bonds, tau bonds or banana bonds; whatever you might like to call them were ...
- 83.7k
15
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Structure of Benzyne
Yes, but.
Yes, in the conventional low-level models, one would consider the two carbons in benzyne you mentioned as sp-hybridised. And that does mean that their orbitals seem to be pointing the wrong ...
- 66.4k
15
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Is the phenyl cation or ethynylium more stable?
Preamble
As trivial as this question might seem, it is not. It should certainly never be asked in at an exam level lower than basic quantum chemistry.
Any of the tempting explanation schemes will ...
- 43.5k
15
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How can the hybridisation schemes of transition metal complexes be determined?
Firstly, note that hybridisation theory as applied to transition metal complexes is an incorrect, flawed theory. It is an attempt to rationalise experimental observation (e.g. geometries), but in the ...
- 70.1k
14
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What is the hybridization of terminal fluorine atoms in molecules like boron trifluoride?
TL;DR: As a rule of thumb, terminal (heavy) atoms are almost always best described as having sp hybrid orbitals (at the most).
For more on this, I refer you to my answer on What is the hybridization ...
- 43.5k
14
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Predicting sigma bond overlap strengths of s-s, p-p, s-p, sp-sp etc
I think the issue might be what orbitals are being referred to. Both books could be correct if they are referring to different $\mathrm{p-p}$ overlap. For example, suppose two atoms are bonding along ...
- 11.5k
13
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Are the bonding orbitals in methane equivalent - photoelectron spectrum
This question goes along the line of what does it mean when it is said that an sp3 orbital has 25% s-character. It also intrigued me so I have tried to find answer, which would not break my hybridised ...
- 4,487
12
votes
Are the bonding orbitals in methane equivalent - photoelectron spectrum
The short answer is that's not how photoelectron spectroscopy works. It's a one-photon spectroscopy.
You have a sample of $\ce{CH4}$ in this case, and you shoot different energy photons at the sample....
- 27.5k
12
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Why does hybridization significantly matter for organic chemistry?
Orbital hybridization is mostly useful in the rationalisation of molecular geometry. In fact it was invented by Linus Pauling for this purpose: to rationalise structures of organic molecules using the ...
- 18.7k
12
votes
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When is there hybridization and when is there no hybridization?
As Ivan already mentioned, hybridisation is not a physical phenomenon. Physically, the most accepted theory at the moment is that you have nuclei and the electrons roam freely in between them, forming ...
- 66.4k
12
votes
What is the hybridisation of trifluoromethyl free radical?
Hyperconjugation between the orbital that contains the lone pair and the $\ce{C-F}$ antibonding orbital contributes to the pyramidalization of $\ce{CF3^·}$ radical:
In the planar geometry the ...
- 14.2k
12
votes
Hybridization of sulfur in sulfur dioxide
The structure of sulfur dioxide ($\ce{SO2}$) is quite complicated.
The image from socratic.org* explains it quite well, please find the $\ce{SO2}$ hybridization diagram via the Internet Archive.
As ...
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