Input File Format
============================

.. contents::
   :local:

In Qbics, most computational settings are given in a single input file. The following one is a basic Qbics input file:

.. code-block:: bash
    :caption: water.inp
    :linenos:
 
    # A B3LYP/cc-pvdz calculation for water.

    basis
        cc-pvdz
    end
    
    scf
        charge  0 # Total charge.
        spin2p1 1
    end
    
    mol
        O   0.00000000000000      0.05011194954430      0.05011194954224
        H   0.00000000000000     -0.06080277603381      1.01069082652926
        H   0.00000000000000      1.01069082648951     -0.06080277607149
    end

    task
      energy b3lyp
      opt b3lyp
    end

- You can insert comments at any place using ``#``.
- Statements like ``mol ... end`` are called a keyword block. In this example, we have ``basis``, ``scf`` and ``mol`` blocks. They give details about how calculations should be done by Qbics.
- A special block is ``task``. It tells Qbics what tasks to do. In this example, there are two calculations: ``energy b3lyp`` and ``opt b3lyp``. They will be done one-by-one.