HOMO and LUMO Molecular Orbitals for Conjugated Systems by Leah4sci

Leah4sci.com/MO... presents: HOMO and LUMO Molecular Orbitals for Conjugated Systems
Need help with Orgo? Download my free guide ’10 Secrets to Acing Organic Chemistry’ HERE: leah4sci.com/or...
Molecular Orbital theory can be one of the most complicated and frustrating topics to study in chemistry, especially when the focus is on the math and physics behind it. This video offers a logical overview of HOMO and LUMO molecular orbitals, especially as it applies to conjugated systems in organic chemistry reactions and mechanisms. You’ll learn how to draw and understand MO diagrams for systems with more than two electrons in molecular orbitals through the use of a simple analogy.
In this video:
[0:37] Description of HOMO and LUMO
[2:36] Electrons in the Highest and Lowest Energy
[5:16] Alignment and Flow of Electrons
[8:25] Understanding HOMO and LUMO Concept
Links & Resources Mentioned In This Video:
Molecular Orbital Theory Leah4sci.com/MO...
Resonance Structures in Organic Chemistry Leah4sci.com/Re...
Diels Alder Reaction and Mechanism Leah4sci.com/Di...
This is part of the Molecular Orbital Theory Mini Series. Catch the entire MO Theory Video Series on my website at leah4sci.com/MO...
Follow along with your semester by using my Orgo Syllabus Companion: leah4sci.com/sy...
For more in-depth review including practice problems and explanations, come join my online membership site the organic chemistry study hall: leah4sci.com/join
For private online tutoring visit my website: leah4sci.com/or...
For questions and comments, find me on social media here:
Facebook: / leah4sci
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Instagram: / leah4sci
Pinterest: / leah4sci

[@Pete-da-peter]

This is the same thing my professor was doin in class today, the difference is she just have the gift of explanation, even an unborn child can understand. Thank you my dear love. You are a God given gift.

[@Leah4sci]

Thank you! I'm sorry that your professor wasn't able to explain this (I had the same issues in undergrad). But I'm glad my videos can fill that gap for you

[@dontmesswiththeriddim2699]

This was a mind boggling topic, I never thought I could understand it until you swooped in and saved the day. Thanks Leah for your great help!!

[@Leah4sci]

Wow! Glad it was helpful!

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Well done

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@@Leah4sci well done 👏👏

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Your videos saved me during my days in undergrad and now I still go back to your videos as I'm studying for my board exams. Thank you so much! You're the best!

[@Leah4sci]

Best of luck! Let me know how they turn out!

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I want to give you a hug right now 😭😭😭 thank you

[@Leah4sci]

Aww, sending virtual hugs to you, you're so welcome!

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Absolute great teacher. Science can be fun and explained well besides reading the lines extracted from theories and lessons and this is what she proved. I will go over her videos more in the future and have subscribed to her. I wonder why would someone dislike such a legendary explaination.

[@Leah4sci]

Wow, thanks so much for your kind words!

[@asrarqueisi]

You’re ability to teach this really rigorous course always amazes me till this day. I’m so happy I came across your videos.

[@Leah4sci]

Aww thanks for your kind words, and I'm so happy you found my channel, too!

[@kenjidroge1330]

hey i’m german and i didn’t understand this topic until i watched your video. there was no german equivalent and i found this video which helped me a lot. thank you very much :)

[@Leah4sci]

Glad I could help!

[@sayanwatching]

This was really something different , like my professor also told something like that but he didn't use pictures we we had to imagine of something we have never seen . But you took it a step further and again thank you ma'am for these simple words that's all we need . ❤❤❤

[@Leah4sci]

I'm glad you found it helpful! I think "seeing" it makes it so much easier to understand. It's why I like to learn from videos!

[@cassied9327]

I haven’t watched Leah4sci since I was just starting community college. Now that I’ve transferred to university I’m just so happy to have this resource to help me review and get back up to speed

[@Leah4sci]

So happy to help get you back on track!

[@anthonyokpe]

I wish I could like this video twice. As a chemical engineering master student studying in Germany, I wish you could just teach my Advanced Inorganic Professor. I just used this to learn all of the concepts my Inorganic CHM Prof has been trying to say all semester. I have my exams in days. Thanks Leah.

[@Leah4sci]

You're very welcome! So glad the video helped clear things up for you. Best wishes on your exams, let me know how it turns out for you!

[@eleanor5675]

My worksheet confused me completely when it got to this and I couldn't wait for my professor to actually bring these problems up in class. Thank you for the great explanation!

[@Leah4sci]

You are so very welcome and YAY! I'm thrilled to hear that I cleared up the confusion for you!

[@sanzedtaief]

Thank you Ma'am. Your lecture really helped me with my undergrad studies and cleared my doubts and to teach my students with more confident. Hope you will reach 1 million subscribers soon ❤️❤️. Love from Bangladesh 🇧🇩

[@Leah4sci]

I'm so happy to help!

[@gabe2632]

This might be the best series of videos I've ever watched. Explains everything so well and makes everything easy to understand. THANK YOU!

[@Leah4sci]

Wow, you're very welcome and thanks so much for your kind words!

[@dribrahimel-nahhal2477]

Thank you pretty much Leah for all of your videos. I enjoy your simplistic way of simplifying complicated topics such as organic chemistry. Love from Palestine

[@Leah4sci]

You're very welcome!

[@ryanmoen5942]

I am in my last week of O-chem 1 and have no time to let that "ah-ha" moment happen before the final. This is amazing. TopHat really failed to teach this concept so clearly. THANK YOU

[@Leah4sci]

You're very welcome! Glad you found the video helpful.

[@nevermore7367]

I used to watch your videos in 2016-17, when I was preparing for my med school entrance exam. I never really liked Organic Chemistry, but you made it tolerable lol I'm now in my third year of med school. Thank you! :)

[@Leah4sci]

Oh wow, thanks so much for commenting and letting me know. If you're interested in sharing more of your journey, please contact me at leah4sci.com/contact

[@TacosvsCreepers123]

you absolutely ate down w this video my final is literally in 30 minutes, this was literally one of the first concepts we learned in orgo and it hasnt clicked until i watched this video

[@Leah4sci]

So glad I helped clear it up! Hope your final turned out well for you!

[@faithj6730]

Thank you for the breakdown!!!! In my class, we get so far with the fancy concepts that I needed a refresher on the concept. Much appreciated Leah!

[@Leah4sci]

You're very welcome! I'm glad to hear that I helped clear up the concept for you.

[@marymohd4553]

Omg Thank you so much for making this video! This concept was so difficult for me to grasp from my lecture, and your video literally made me feel my fog of confusion disappear! I actually got so excited when I was able to understand this :)

[@Leah4sci]

That's exactly how I felt when I finally found another way to think about it. So glad it helped you make sense of this craziness :)

[@anirbanhait5998]

This explanation is very helpful to me.Actually real world examples really help to understand the mistry of Chemistry.

[@Leah4sci]

Glad it was helpful!

[@vishnuprasad4381]

Thanks for your great help Mam and it is easier then I thought Was difficult without knowing the proper concept any proper explanation But after your explanation this is the most funniest and For my exam thank you mam ❤❤❤

[@Leah4sci]

Always happy to help! You're so welcome.

[@vishnuprasad4381]

@@Leah4sci welcome mam

[@thebritishunicorn7936]

thank you this is god sent :)

[@Leah4sci]

You're welcome!

[@xuanyang3107]

I like the way you illustrate. It's very clear and I can feel the passion. Thank you!

[@Leah4sci]

You're so welcome, and I'm glad to know that my passion for the subject comes through!

[@Mayuriitd]

Thank you very much mam 🙏. Really you explained very well and first time I was able to watch full video. And understood all the concepts.

[@Leah4sci]

So glad it helped clear things up for you!

[@Juliquiny]

I'm speechless! This video is truly a masterpiece! thank you so much!

[@Leah4sci]

So glad you found it helpful

[@MalikBilal0144]

amazing lecture i am graduate in inorganic chemistry, it felt a bit hard to understand the theme of such a confusing topic. respected mam you made it so clear that now it is on fingertips.

[@Leah4sci]

Glad this helped

[@miss_nerdy1716]

not sure if I understood it completly but it sure was more entertaining and fun to watch than my chemstry readings in uni love from germany

[@Leah4sci]

Glad you liked it!

[@furfoxsake1175]

I always let out a sigh of relief when I need to study an ochem concept and one of your videos pops up in the search results.

[@Leah4sci]

Aww, that makes me so happy to hear! You can also refer to leah4sci.com/syllabus

[@raquelsmithphd5813]

Brilliant! thank you. Not being a chemist, I am inspired to understand human behavior based on your theoretical framework and explanation. Many thanks!!

[@Leah4sci]

You're very welcome!

[@SoormayeeJoshi]

Thank you so much! This cleared a lot of confusion in my head ☺

[@Leah4sci]

Glad it was helpful!

[@manmohansavita3676]

Thank you so much mam Please make video s on remaining organic name reactions and mechanism

[@Leah4sci]

Thanks for the recommendation. I post free videos as I have time and am always looking for suggestions. For more help with this topic in the meantime, contact me through my website: leah4sci.com/contact Also check out this: leah4sci.com/naming-organic-compounds-iupac-nomenclature/

[@emilyh3644]

My notes so I can understand this video: # of atomic pi orbitals equals the # of pi molecular orbitals. So if you have six pi electrons (from three pi bonds) that equals six pi molecular orbitals. This can be represented by a group of friends. Most stable is all of the friends getting along (completely bonding and low energy and happy), least stable is every single friend is not getting along with anyone (completely antibonding and high energy and unhappy). Nodes represent distance between two friends, increases energy and moves them to more antibonding level. And... I was just focusing on your great examples for the rest of the video. LUMO and HOMO make so much sense and the resonance example really helped with understanding the relative energies. Thanks. :) Now I feel ready for Diels-Alder stereochemistry and endo/exo stuff and how the pi orbitals overlap.

[@Leah4sci]

Awesome idea! And so glad I helped you understand!

[@motivation_daily333]

Had this type of question on my test and literally helped so much

[@Leah4sci]

Yay, so glad it helped!

[@_ryle.]

you are an amazing instructor!!! this made so much sense with your analogies 😁thank you!!! ❤️❤️

[@Leah4sci]

Aww, thanks so much! Glad it was helpful!

[@zombie60223]

I was freaking out about my chemistry problem set, thank you so much for making this! You're a life saver❤️❤️❤️

[@Leah4sci]

Always glad to help! You're welcome.

[@abhinavraje3614]

My most favourite organic chem teacher

[@Leah4sci]

aww thanks :)

[@leonardoorsi1198]

Your explanation was so cute that I actualy started to like this topic

[@Leah4sci]

Thank you! I don't aim for 'cute', but I'll definitely take it! Lol.

[@NawazKhan-wn9mq]

I understand first time the Lumo And Homo concept thank you ❤so much

[@Leah4sci]

So glad this helped you understand what I (and many students) found to be quite a tricky topic

[@rakeshrajpoot7117]

l watching from india!! I like your videos, much usefull, the way of exaplaining is outsatnding. I like that😊

[@Leah4sci]

Thanks! 😃Glad you like them!

[@Drift1]

Thank you Leah for explaining this so simplistically!

[@Leah4sci]

You're so welcome!

[@borzoo]

thank you for great lecture

[@Leah4sci]

You're welcome!

[@t.lwillow4581]

Wow. I finally understand how it works. Thank you so so much.

[@Leah4sci]

You're so very welcome, I'm glad I could help you understand.

[@johnalexandermoralesmorale1141]

Thanks, I'll have a test on the topic soon.

[@Leah4sci]

Happy to help you prepare!

[@kashiish2]

This was so clear and useful! Thanks!

[@Leah4sci]

Thank you! So glad you found it helpful

[@lie-o-phobicsoul5404]

Thnx for this video, learned a lot

[@Leah4sci]

Glad to hear it!

[@kayth1373]

finally understand this concept thank you

[@Leah4sci]

So glad!! You're welcome.

[@DeniseP]

So crazy im literally doing this right now and the email popped up. LOL its like you heard me.

[@Leah4sci]

Perfect timing, love it! Hope it helps you better understand this crazy topic Denise

[@DeniseP]

@@Leah4sci it really did and I think using the little people helps a lot as well. Thank you 🙏🏼

[@andrewcheesman533]

LITERALLY SAME!! My final on Wednesday has HOMO and LUMO on it! Thank you!!

[@nicholasnthengemutinda]

wow, you''re the guru.... i gerrit now

[@Leah4sci]

Lol, glad to help

[@Lauren-jr4is]

This is an incredible explanation. Thank you so much!!

[@Leah4sci]

You're very welcome!

[@husseinward3377]

Thank you .great teacher organic chemistry

[@Leah4sci]

You are very welcome

[@AsK_6487]

Where were you when I was doing this back in 2007?!?!!! 😭😭😭😭 I remember staying up late drawing circles, almost making holes in my notes just to make some sense into this! Hahahaha 🤣

[@Leah4sci]

Oh no! I'm sorry you had such a tough time then, but happy to help you out now!

[@zyanumer7615]

Thank u sooo much ma'am .. I find it too hard to learn .. I can't even grasp the core concept of this but after this lec I'm really happy ... I got the concept 💜

[@Leah4sci]

that's awesome

[@OdaNobunaga1995]

Thank you Leah 😊

[@Leah4sci]

You are so welcome!

[@UltimateXMAN]

Fantastic video. Thank you for the clarification.

[@Leah4sci]

My pleasure! I'm glad it cleared things up for you

[@temidayooke6270]

Omg you explained this so well

[@Leah4sci]

Thanks so much :)

[@aryansudan2239]

thanks i finally got this after watching ur video

[@Leah4sci]

Glad to help!

[@sathvikagandavarapu5813]

You are a legend and the best!

[@Leah4sci]

Aww thank you!

[@saidamzil4732]

Thank you!!!! cleared my doubts for HOMO & LUMO

[@Leah4sci]

You're very welcome, so glad I helped clear things up for you!

[@pradeepgunawardana4691]

Very very clear explanation and well understood the theory. Thank you very much !

[@Leah4sci]

You're so welcome!

[@almosteverthing5228]

Stay Blessed and Healthy Teacher📀❤

[@Leah4sci]

thank you, same to you

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You are my biggest life saver!!! 🥰🥰🥰

[@Leah4sci]

So happy to help!

[@farhanawali4008]

Beautifully explained.Thanks

[@Leah4sci]

My pleasure, so glad you liked it!

[@tanay128]

U made it absolutely clear ... Great explanation ! Loved it🙏...

[@Leah4sci]

So glad it helped you understand!

[@merry9178]

Mind blowing explanation

[@Leah4sci]

Happy to share!

[@shitalsharma8445]

Thank you so much ma'am...❤️

[@Leah4sci]

You're so welcome!

[@nathanm8234]

You are the best I’m learning this right now!

[@Leah4sci]

Perfect timing Nathan! hope this helped

[@Odiainjapan]

Very informative and helpful. I just understood one of the concepts that I used get scared of. 👍 Thanks. Attagirl. 😊😊

[@Leah4sci]

You're so welcome! Glad it was helpful!

[@saraswathisreenivasulu5460]

Mam I am so greatful to watch this and finally i have cleared my doubts regarding this topic.but i have one more doubt.I understood electrons location in the HOMO and resonating Structure.butthe electrons location in the LUMO and the highly unstable orbitals,is there any possibility to form radicals.

[@Leah4sci]

I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

[@dapadmavathi684]

Excellent presentation

[@Leah4sci]

Thanks!

[@jeallybeanjohns2958]

Thank you very much ❤

[@Leah4sci]

You're welcome 😊

[@amicsora272]

I've watched so many videos on this topic and still had such little understanding of MOs and their diagrams but OMG THIS MADE SO MUCH SENSE THANK YOU SO MUCH!!!!!!

[@Leah4sci]

Yay! So happy to help!

[@Maureen_Mutheu]

Woowww... such a great explanation

[@Leah4sci]

Glad it was helpful!

[@rosalindkidwell2483]

Great explanation - thanks a ton

[@Leah4sci]

You're so welcome!

[@travisdean6063]

This was helpful.

[@Leah4sci]

Glad you liked it!

[@shoaibahmed1115]

In case of 1,3 butadiene, (IN GROUND STATE UNDER THERMAL CONDITION) si 2 is HOMO and si 3 is LUMO. (IN EXCITED STATE UNDER PHOTOCHEMICAL CONDITION) si 3 will be HOMO because an electron jumps from si2 to si3. So in this state what will be the LUMO?

[@Leah4sci]

I'm sorry, but I don't offer tutoring over social media. For help with questions like this and more, I recommend joining the organic chemistry study hall. Details: leah4sci.com/join or contact me through my website leah4sci.com/contact/

[@ashokpullemla16]

Good explanation madam🙏

[@Leah4sci]

Thank you 😃

[@291ayl]

Leah, you are amazing... but I was wondering if you could clarify one thing for me... why are we only using P orbitals? Are S orbitals unable to participate?

[@Leah4sci]

Pi bonds are formed, specifically, by the overlap of unhybridized p orbitals. When we focus on the conjugated pi electrons in a system, we're looking at those electrons existing in p orbitals alone.

[@291ayl]

@@Leah4sci got it... thank you so much!

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You are AMAZING❤❤❤❤❤thankssss

[@Leah4sci]

You're so welcome!

[@DaniyalKhan-gt5ol]

Aah! Masha Allah ...... Superb

[@Leah4sci]

Thanks, glad you liked it!

[@zachary1761]

Better than my prof's explanation in a shorter time. It just didn't make sense til this

[@Leah4sci]

Glad to hear it! :)

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i love you. never stop please

[@Leah4sci]

Thank you... But how about we just stick to a professional relationship? Lol

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Its amazing video mem.. Thank you so much😊

[@Leah4sci]

You're so welcome!

[@asifahmedtanmoy]

this is so helpful. Thank you very much Ma'am

[@Leah4sci]

Glad it was helpful!

[@pexaminer]

Great video!

[@Leah4sci]

So glad you liked it!

[@yase672]

you are great tutor thanks!

[@Leah4sci]

You are welcome!

[@Thinker.575]

Thank you very much this help me a lot

[@Leah4sci]

You're welcome, so glad it helped!

[@devakideshmukh5871]

THANK YOU ❤️😭

[@Leah4sci]

You're so welcome!

[@HerjokAgot-k4k]

This is genius!!

[@Leah4sci]

Glad you like it!

[@gupta-pw5xb]

This is soooooo good Thank you so much 😄😊

[@Leah4sci]

You're so welcome!

[@InertialFrameObserver]

Thank Youu

[@Leah4sci]

You are very welcome!

[@erikag703]

thank u, u saved our lives

[@Leah4sci]

You're very welcome

[@carolineisemann4105]

This is great. Thank you!

[@Leah4sci]

You're very welcome!

[@rizwanilyas4289]

Highly helpful 🙂

[@Leah4sci]

Glad you liked it!

[@brendangodwin6302]

This helped so much

[@Leah4sci]

Awesome!

[@karanbhanushali6756]

I had a question that if a molecule has highest energy then it should be lowest occupied because if we consider two paths one of highest energy and other of lowest energy so for electron to reach an the orbital the lowest energy one would be easier to reach and thus according to this logic the one who has lowest energy should be highest occupied because it has a more simple path to reach for electrons compared to those one who has more energy but the above theory is contradicting it

[@Leah4sci]

I'm sorry, but I'm not understanding your question. At which specific point in this video do you have a question?

[@karanbhanushali6756]

Regarding the concept of Homo and Lumo I am relating their occupancy with energy level

[@Ranjanakumari-fj6vo]

@@karanbhanushali6756 ur confused see in respect of electrons not energy🤣

[@karanbhanushali6756]

@@Ranjanakumari-fj6vo Ok

[@zyanumer7615]

Ma'am had u given any lec on hyperconjugation??

[@Leah4sci]

yes

[@finno-px6of]

Amazing!

[@Leah4sci]

Thanks!

[@ehoma]

this is very intresting

[@Leah4sci]

Isn't it? Difficult though

[@alexngasa5319]

Thanks madame

[@Leah4sci]

You're welcome!

[@Htmal-s2l]

Thanks 👍🏻

[@Leah4sci]

You’re welcome 😊