ChemServerOnline DFT calculations
Density functional theory for your ligands and small molecules without installing a quantum chemistry package: optimized geometries, energies, orbitals, charges and spectra, set up from a SMILES string or a structure file.
Available on request. DFT runs on dedicated compute servers and is opened per account. Email chris@chemserver.online with your molecules and the properties you need.
Input
- SMILES (one molecule per line), a drawn molecule, uploaded XYZ, SDF, MOL, MOL2 or PDB files, or a ligand from My Files.
- Charge and spin multiplicity.
- Starting geometry from RDKit ETKDG with MMFF94, GFN2-xTB preoptimization, or your own coordinates.
- Optional CREST conformer search, then DFT on the lowest conformers.
Level of theory
| Choice | Options |
|---|---|
| Program | Psi4, PySCF, ORCA, xTB |
| Method | DFT, Hartree-Fock, MP2, GFN2-xTB |
| Functional | B3LYP, PBE0, ωB97X-D, M06-2X, CAM-B3LYP, TPSSh, PBE, r2SCAN-3c, B97-3c |
| Basis set | 6-31G(d), 6-31+G(d,p), 6-311++G(d,p), def2-SVP, def2-TZVP, def2-TZVPP, cc-pVDZ, cc-pVTZ, aug-cc-pVDZ, STO-3G |
| Dispersion | D3(BJ), D4, D3 zero damping |
| Solvation | Gas phase, CPCM, SMD or IEFPCM in water, methanol, DMSO, chloroform and other solvents |
Calculations
- Single point energy, geometry optimization, and optimization with frequencies.
- Frequencies for IR spectra and thermochemistry (zero point energy, enthalpy, Gibbs free energy).
- Excited states by TD-DFT for UV Vis spectra.
- NMR shielding, transition state searches and relaxed scans.
Properties
- HOMO and LUMO energies, the HOMO LUMO gap and frontier orbital surfaces.
- Electrostatic potential maps and dipole moments.
- Mulliken, Löwdin, Hirshfeld, CHELPG and RESP partial charges.
- Global reactivity descriptors (chemical hardness, softness, electrophilicity) and Fukui functions.
- Natural bond orbital analysis, polarizability and NMR chemical shifts.
- Output files, cube files for orbitals and plots as PNG, SVG or PDF.
Where DFT helps in drug design
- Accurate ligand geometries and conformer energies before docking.
- RESP charges for unusual ligands in molecular dynamics.
- Reactivity and stability trends across a series of analogues.
- Comparing calculated IR, UV Vis or NMR spectra with your experiments.
Need DFT for your molecules?
Tell us the molecules and properties and we will open DFT for your account.