Chemistry Lab Computational chemistry lab

Integrated Quantum & Computational Chemistry Lab

Three unified studios on one platform: draw publication-ready chemical structures and reaction schemes, generate and run ORCA calculations with cloud auto-recovery, and analyze 3D quantum geometries, UV-Vis spectra & reaction thermochemistry.

An open-access academic suite for quantum and computational chemistry researchers - developed by ABDULSALAM S. HASAN · Mosul, Iraq.

📄 Download Academic Manual (.docx)
Lookup & analysis

Molecule Explorer

Enter a compound name, SMILES, or InChI - get a clean structure plus its physical and chemical properties.

Reaction schemes

Reaction Drawing

Separate reactants with a “+”, and enter products in the matching field. Names and SMILES can be mixed freely.

💡 Put the number of moles in front of a species: 2 H2 + O2, 2H2O, or fractional 1/2 O2. Names, formulas, SMILES, and InChI all work seamlessly.
How to write an equation - syntax, examples, and what you get back

1. The shape of an equation

Put the reactants in the left box and the products in the right one. Separate species with +. The arrow is the gap between the two boxes - you do not type it. 

Reactants:  CH4 + 2 O2
Products:   CO2 + 2 H2O

2. Labels above and below the arrow

Use Above arrow and Below arrow for catalysts, solvents, temperature, pressure, light, or other reaction conditions. The arrow will expand to fit the longer label. Type ^ immediately before a superscript segment; the marker itself is removed and the superscript ends at the next space. Example: H^+ displays H+, and SO4^2- displays the charge as superscript.

2. Number of moles (stoichiometric coefficient)

Write the number in front of the species. Three forms are accepted:

  • 2 H2O - a number, a space, then the species.
  • 2H2O - glued to a formula. Only read as a coefficient when what follows is a bare formula, so 2-butanone, 1H-pyrrole and 13C-methanol keep their names intact.
  • 1/2 O2 or 0.5 O2 - a fraction, as thermochemistry is usually written.

A species with no number in front of it counts as 1.

3. Naming a species

Any of these work, and they can be mixed in the same equation:

  • Name-water, acetic acid, benzene (looked up in PubChem).
  • Formula-H2O, CO2, NaCl.
  • SMILES-CCO, c1ccccc1, CC(=O)O. Best for anything with a specific structure.
  • InChI - paste it starting with InChI=.

A few strings are both a valid SMILES and a common formula - CO is methanol as SMILES and carbon monoxide as a formula. Those are read as the formula and the page tells you which reading it used, so you can switch to an unambiguous SMILES if it guessed the other way.

4. What gets drawn, and what gets written

Small unambiguous species are written as formulas - O2, H2O, CO2, NH3 - because a skeletal drawing of O2 is two letters and a line, taking the width of a benzene ring to say less. Everything else is drawn as a structure. Ethanol is always drawn, never written as C2H6O: dimethyl ether has that same formula, so writing it would throw away exactly what the drawing is for. Untick Write small molecules as formulas to draw every species instead.

5. The balance check

After drawing, every element and the total charge are counted on both sides using your coefficients. If they do not match you are told which element is in excess and on which side. The scheme is still drawn - a mechanism step or a fragment is legitimately unbalanced, and the problem this guards against is not noticing.

6. The downloaded .rxn file

You get an MDL RXN V2000 file, which is the format ChemDraw, MarvinSketch, Avogadro and RDKit all import. That format has no field for a coefficient, so the convention every reader understands is used instead: the structure appears once per unit. 2 H2O puts two water molecules in the file, and ChemDraw will show two of them rather than the text “2 H2O”. The stoichiometry is there and machine-readable, just not as a numeral. A fractional coefficient cannot be written at all, so all coefficients are multiplied up to whole numbers - the ratios are unchanged, and the factor used is reported.

The file is checked before you are offered it: the $RXN header, the component counts matching the blocks that follow, and a M  END terminator on every structure. The badge under the drawing reports that check.

7. A worked example

The complete combustion of benzene, with the coefficients balanced:

Reactants:  2 benzene + 15 O2
Products:   12 CO2 + 6 H2O

Benzene is drawn as a ring; O2, CO2 and H2O are written as formulas; the badge confirms the equation balances; and the .rxn file contains 2 benzenes, 15 oxygens, 12 carbon dioxides and 6 waters - 35 structures in total.

Computational chemistry

ORCA 6 Input Generator

A guided wizard with sequential option windows - produces an .inp file that matches exactly what you chose, with no silent additions.

No structure selected yet.
Remote execution

Launch ORCA on Kaggle

Packages your input file into a Kaggle notebook of your own and runs it on Kaggle's free compute, automatically relaunching until convergence whenever a session runs out of time (11h45m) or out of scratch disk space - each new session picks up from the last completed step.

This feature does not distribute the ORCA program. You must provide your own licensed ORCA package (downloaded from the official ORCA forum after your own registration) - either as a private Kaggle Dataset attached to the job, or via a Google Drive / direct download link that the job downloads and extracts into /tmp itself. Your credentials are used once to submit the job and are never stored on the server - only in your own browser, if you choose to remember them below. Both the new single API token and the legacy username/key from Kaggle's Settings → API page are accepted in the field below.
📋 How do I get my Kaggle username and API key/token?

1 - Create a free Kaggle account

If you don't have one yet, go to kaggle.com and sign up (email, Google, etc.), then verify your email address.

2 - Open Settings → API

Once signed in, click your profile picture in the top-right corner → Settings, then scroll down to the API section.

3 - Create your key/token

Click Create New Token. Kaggle issues a token that looks like KGAT_… - paste it into the "API key / token" field below, together with your Kaggle username in the field above it.

Prefer the older format? The same page also has a Legacy API Credentials section with a Create Legacy API Key button, which downloads a kaggle.json file holding your username and a 32-character key. Either format is accepted here - just always pair whichever one you use with the username shown on that same Settings page.

4 - Verify your phone number

Jobs submitted from here run with internet access turned on (needed to fetch/extract your ORCA package and install a couple of small Python packages). Kaggle only allows internet access on phone-verified accounts, under Settings → Phone Verification. Skipping this is the single most common reason a first submission fails with no obvious explanation.

Treat this key/token like a password: anyone who has it can act as you on Kaggle. It's sent only for the moment of a request and is never written to a database or kept long-term on this server; checking "remember me" saves it only in your own browser's local storage. Full details on the Legal, Privacy & Disclaimer page.
Signing in also pulls back any jobs already submitted from this Kaggle account, so you can get back to them even after clearing your browser data or switching devices.
⚛️ How do I get ORCA, and why does it have to be the Linux version?

What ORCA is

ORCA is a professional quantum-chemistry program developed by Prof. Frank Neese's group and distributed by FACCTs GmbH. It's free for academic and personal, non-commercial use - but it is closed-source and its license forbids redistribution, which is exactly why this site can't just hand you a copy and instead walks you through getting your own.

1 - Register on the ORCA Forum

Go to orcaforum.kofo.mpg.de and create a free account, then confirm your email - registration only completes after that step.

2 - Accept the license and open Downloads

Once logged in, open the forum's Downloads section. You'll be asked to read and accept ORCA's End User License Agreement (EULA) before any file becomes available.

3 - Pick the Linux build - this is the part that matters here

ORCA ships builds for Windows, macOS, and Linux. This launcher runs your job inside a Kaggle Notebook, which is a cloud machine running Linux - not Windows, not macOS. A Windows .exe or a Mac binary is a different executable format that a Linux machine simply cannot run; only a Linux-compiled build will actually execute there. So from the list, pick the one described along the lines of:

  • Linux, x86-64, shared-version, .tar.xz Archive - the "dynamically linked" build, paired with an OpenMPI version shown right in its filename (e.g. orca_6_..._linux_x86-64_shared_openmpi....tar.xz).

If a listing is marked as requiring AVX2 and you aren't sure that applies to you, the plain (non-AVX2) Linux shared build is the safer default.

4 - Provide ORCA via your preferred source

  • Option A - Kaggle Dataset: Upload the Linux .tar.xz to Kaggle as a private Dataset and supply its identifier (e.g. username/dataset or dummy example jon534/orca6) or full URL.
  • Option B - Google Drive / direct link: Provide a direct download URL to your Linux ORCA archive.
You're responsible for using ORCA only under your own registration and in line with its EULA (academic/personal use, non-commercial, no redistribution). This site has no part in, and takes no responsibility for, how you obtained or use your copy - see the Legal, Privacy & Disclaimer page.
Track progress

My Jobs

Jobs submitted under your signed-in Kaggle account. Status refreshes automatically; a download link appears next to a job's name once its results are ready. A job that had to continue in a fresh session stays a single entry here and follows its newest notebook. Deleting a job here also permanently deletes its notebook - and every continuation it spawned - from Kaggle.

Sign in with your Kaggle account on the Kaggle Launcher tab to see your jobs.
Quantum Chemistry Engine

ORCA Calculation Analyzer & 3D Viewer

Parse any ORCA calculation output file (.out, .log, .property.txt) or compressed archive (.zip, .rar) to inspect 3D molecular geometries, frontier molecular orbitals (HOMO/LUMO), UV-Vis spectra with real-time Gaussian convolution, and CDFT reactivity descriptors.

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Drag & drop ORCA output files (.out, .log, .property.txt) or archive (.zip, .rar) here or click to browse your computer
📝 Or paste ORCA output text directly
Thermodynamics

Reaction Thermochemistry & Energetics

Calculate reaction enthalpy ΔH°, Gibbs free energy ΔG°, entropy ΔS°, and equilibrium constant Keq from parsed ORCA outputs with stoichiometric validation.

Chemical Reaction Equation:
2 H2 + O2 ➔ 2 H2O
📦
Quick Batch Upload (ZIP / RAR Archive): Drop an archive containing all species ORCA output files - we'll auto-extract and match them to your reaction.
🧪

Reactants

Define reactant species, stoichiometric coefficients, and attach their ORCA output files or Kaggle jobs.

⚗️

Products

Define product species, stoichiometric coefficients, and attach their ORCA output files or Kaggle jobs.

🌡️ Optional: Calculate at Custom Temperature & Pressure (Gas Phase / Solvation-Free RRHO)

By default, the platform extracts and applies the exact thermodynamic conditions (T, P) reported directly in your ORCA output files. If you wish to recalculate the Ideal Gas / Rigid-Rotor Harmonic Oscillator (RRHO) statistical thermochemistry at a non-standard temperature or pressure (in the absence of implicit solvation models), enable custom conditions below: