Introduction to Symmetry Operations and Point Groups

[@EKOxL3G3ND]

You just saved my life for an exam I have today, lecture notes and office hours haven't helped at all, but this made it so much easier to understand.

[@CCDCCambridge]

Best of luck in your exam!

[@jamesbean9396]

Amazing help! Symmetry can be a mind bender and there are very few good videos on the matter. Cheers :)

[@Somebodyelse141]

I've got a test tomorrow, and I keep messing up

[@kneelisun]

Me too

[@tarun.n726]

Who doesn't 😂

[@AMRO_KHALID_ALIFAYAD]

your explanation is just amazing.

[@MichaelJamesMcGlinchey-wu3bs]

A very clear exposition of the principles of symmetry. I will show it to my students. But please do not confuse the words "principle" and "principal". You should refer to the C6 in benzene as the "principal" axis.

[@suelengabrielaa]

This was so clear and easy to understand, thank you!

[@Patrick-vv3ig]

I am currently reading through Atkin's Molecular Quantum Mechanics book. The chapter on Group Theory is awfully abstract and hard to visualize (at least for me). These animations help a lot. Thanks!

[@cristianogomesdefaria303]

Realmente as figuras não são muito elucidadtivas nesse livro texto.

[@sayanipal7793]

Loved it. Thank you for the video.

[@masheroz]

Ah! I've just gotten used to H-M notation, now I need to learn Schoenflies!

[@vislagama]

great video really good way of teaching

[@wendewows1743]

Not enough information, the examples go through too quickly, couldn't follow properly.

[@CCDCCambridge]

Hi - we also have a PDF that walks through this topic. Click on "Introduction to Symmetry Operations and Point Groups" here: www.ccdc.cam.ac.uk/Community/educationalresources/teaching-modules/

[@guccihope6908]

still trying to get my head around horizontal and vertical planes of symmetry

[@user-dd3xz1hb6w]

could you explain why the planes are sigma d but not sigma v? your videos really help me a lot, thank you so much.

[@malikadarashid]

Just did this in class today. Basically sigma v is when the plane cuts along the z axis and sigma d is when it doesn’t.

[@malikadarashid]

In chemistry, sigma (σ) planes of symmetry are used to describe symmetry elements in molecules. The key difference between a sigma d (σd) plane of symmetry and a sigma v (σv) plane of symmetry lies in their orientation and the type of symmetry they represent: 1. Sigma d (σd) Plane of Symmetry: - A sigma d plane of symmetry is a plane that bisects the molecule in such a way that it divides the molecule into two identical halves. - This plane passes through the center of the molecule and is perpendicular to the principal molecular axis, which means it goes through the nucleus of the central atom. - Sigma d symmetry is often associated with linear molecules, such as diatomic molecules like O2 and N2. 2. Sigma v (σv) Plane of Symmetry: - A sigma v plane of symmetry is a vertical plane that passes through the molecule. - This plane is perpendicular to the principal molecular axis and is parallel to one of the molecular bonds. - Sigma v symmetry is typically associated with molecules that have a vertical axis of symmetry, such as planar molecules like benzene (C6H6). In summary, sigma d planes of symmetry bisect the molecule perpendicular to the principal axis, while sigma v planes of symmetry are vertical planes that are parallel to molecular bonds. Understanding these symmetry elements is essential in the study of molecular symmetry and spectroscopy in chemistry.

[@patrickcole3850]

I wish I had that flowchart when I took undergraduate inorganic

[@sugatasanyal2155]

Awesome demonstration.I have subscribed your channel.

[@davidparks2937]

The subscript on sigma seems hard to determine in for example para-dichlorobenzene. There are 3 2-fold rotation axes, so which becomes the "primary" rotation axis in this case?

[@777hfc]

فوتي فالموضوع دغري تكفين الاختبار بعد كم ساعه

[@aliviamazumder3622]

Tysmmmm

[@crazylife4647]

Where you are from?You are so nice at teaching.🎉

[@apimpnamedslickback5936]

Inorganic?

[@bensiu7587]

if the ethane has a staggered structure would it be possible that it possesses a c6 axis rather than a c3?

[@CCDCCambridge]

Hi Ben, Ethane does not have a C6 rotation axis. This is because if you are only rotating the molecule, you need a 120 degrees rotation to overlap with the initial structures, hence the C3 axis. Ethane in a staggered conformation has also an improper rotation axis S6, where indeed the rotation is of 60 degrees, and then the rotation is followed by a reflection, hence overlapping with the initial structure. For a more visual explanation, both the rotation and improper rotation axes are demonstrated on the molecule from 07:10 in this video and they can also be seen in the example on the Symmetry@Otterbein web resource symotter.org/tutorial/ethanes I hope this helps! CCDC Team

[@sciencelessonsinsinhala1540]

Cant see the video clearly

[@CCDCCambridge]

Hello! If the video is not loading well on the device, you can find this introduction also in pdf format on our website. You can find it in the Teaching Modules webpage linked below, where you can download the resource: Introduction to Symmetry Operations and Point Groups. Go here: www.ccdc.cam.ac.uk/Community/educationalresources/teaching-modules/

[@jornadaclassica1160]