Add tutorial

[minhtriet]

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Title: Find the first excitation energy of hydrogen molecule with VQD

Summary:

Relevant references:

Possible Drawbacks:

Related GitHub Issues:

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If you are writing a demonstration, please answer these questions to facilitate the marketing process.

• GOALS — Finding first excitation energy is necessary to model reaction

• AUDIENCE — Chemistry researchers, beginners in quantum computing.

• KEYWORDS — Quantum Chemistry

• Which of the following types of documentation is most similar to your file? (more details here)

• [x] Tutorial
• [x] Demo
• [x] How-to

[sc-64060]

[minhtriet]

Hi can I get a thumbnail please :) Right now "/_static/large_demo_thumbnails/thumbnail_large_vqe_vqd.png is copied from another one

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Deployment Info:

• Pull Request ID: 1075
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[KetpuntoG]

Hi can I get a thumbnail please :) Right now "/_static/large_demo_thumbnails/thumbnail_large_vqe_vqd.png is copied from another one

Sure, let's wait until the end for that

[KetpuntoG]

remember to click on re-request review once you have worked through all the changes 😄

[minhtriet]

Hi @KetpuntoG, I have two questions

1. I realized that in the last cell, I am using the data from Wikipedia (https://en.wikipedia.org/wiki/Hydrogen, search for the word 1312.0 kJ/mol), which is about H2 atom ionization energy (not excitation, still comparable). However, if I take a look at this paper, then excitation energy depends also on the distance R (I assume it is between the two H molecule). Do you happen to know a way to extract that distance in our current set up, or it should be a separate work.
2. Where can I see the compiling error? Github action (https://github.com/PennyLaneAI/qml/actions/runs/8873883902) says everything is ok, but some of the latex broke, and my name as an author doesn't appear. Error messages may help me debug this.

I also resolved most of the comments, but not all. Feel free to close comments / create a new ones :)

[KetpuntoG]

Hi @KetpuntoG, I have two questions

1. I realized that in the last cell, I am using the data from Wikipedia (https://en.wikipedia.org/wiki/Hydrogen, search for the word 1312.0 kJ/mol), which is about H2 atom ionization energy (not excitation, still comparable). However, if I take a look at this paper, then excitation energy depends also on the distance R (I assume it is between the two H molecule). Do you happen to know a way to extract that distance in our current set up, or it should be a separate work.
2. Where can I see the compiling error? Github action (https://github.com/PennyLaneAI/qml/actions/runs/8873883902) says everything is ok, but some of the latex broke, and my name as an author doesn't appear. Error messages may help me debug this.

I also resolved most of the comments, but not all. Feel free to close comments / create a new ones :)

Hi! When you create the molecule, you specify the distance as bond_length.

On the other hand you can check the exact energy by h2.fci_energy.

Your name will not appear yet because you are not in the database but don't worry about that.

To see the details of the error, there is a button to the right of the tests with a red cross that says "details"

I'm going to read the demo again :)

[KetpuntoG]

Please @minhtriet , do not make any changes to the demo today ⚒️

[minhtriet]

Please @minhtriet , do not make any changes to the demo today ⚒️

Hi, sorry. Shall I try to edit it again tmr? Am trying to make the citing work

[KetpuntoG]

Yes sorry, better tomorrow 💪 We are using to much Github resources and tomorrow we have the release

[minhtriet]

I as trying to get some experimental value for the session Setting expectation but has no luck. Perhaps there is a source out there?

[KetpuntoG]

Hi @soranjh , your last comments have been addressed We are ready for the review 😄

[minhtriet]

@ikurecic Thank you, my Pennylane account is at https://www.pennylane.ai/profile/mchau

[ikurecic]

@ikurecic Thank you, my Pennylane account is at https://www.pennylane.ai/profile/mchau

Thanks for that, @minhtriet ! If you can add a photo and short headline to your profile, that would be fantastic.

I see you've been making some changes based on my suggestions. Please feel free to go through the rest of the comments/suggestions, and tag me after you've addressed them. ☺ We're almost done!

[ikurecic]

(The check error is on our end and it will hopefully be resolved soon, so you can go ahead and continue with the comments. ☺)

[ikurecic]

Hi @minhtriet , I see you've been making some updates — could I ask you to look at the remaining suggestions/comments? I think we will be ready to merge this once you do. Please let me know if you have any questions.