To open a checkpoint file, follow:

  1. File
  2. Open
  3. Select the .chk file

Gaussian Logfile

The logfile (.log) contains all of the job information. You should always check the logfile for successful job completion! The “it did something” way is to check the end for an end quote. The “real” way is to check for convergence. That said, not everything that has a Gaussian logfile will have convergence information, but it will have information indicating that what you were doing worked.

IF OTHER PEOPLE ARE GOING TO TALK, CONVERSATION IS SIMPLY
IMPOSSIBLE.
-- WHISTLER'S
PRINCIPLE
Job cpu time: 0 days 0 hours 0 minutes 3.0 seconds.
Elapsed time: 0 days 0 hours 0 minutes 2.8 seconds.
File lengths (MBytes): RWF= 6 Int= 0 D2E= 0 Chk= 1 Scr= 1
Normal termination of Gaussian 16 at Fri Jun 7 10:02:03 2019.

Summary

The summary window contains job information and some results. To access the results summary, follow: Results → Summary. One Eh (hartree) is equivalent to 627.509474 kcal mol-1. There’s a great energy converter page from Colby College that you can use to make this more meaningful to you.

The window contains three tabs, overview, thermo, and opt. Overview is selected. Then the titlecard is shown. Next the file location is listed. The remaining lines contain job information, including: File Type, Calculation Type, Calculation Method, Basis Set, Charge, Spin, Solvation, Electronic Energy, RMS Gradient Norm, Imaginary Freq, Dipole Moment, Polarizabililty, Hyperpolarizability, and Point Group.
The Gaussian summary window.

Vibrations

The vibrations window contains frequency and Raman information. From this window, you can watch animations of stretching and vibrations. To access the window, follow: Results → Vibrations.

The window contains a large table with different vibrational modes shown in each row. The columns include Mode Number, Frequency, Infrared, Raman Activity, Depolar-P, and Depolar-U. Selected rows can be animated using the Start Animation button in the next block, and settings can be adjusted for speed and repetition.
The Gaussian vibrations window.

Charge Distribution

The charge distribution can be plotted on the structure. To access the distribution, follow: Results → Charge Distribution.

Methane is shown with the charges listed on the atoms. Carbon has a -0.794 charge. The hydrogens each have a charge of 0.198.
Charges mapped onto methane.

Cube Data

Different data can be plotted onto the structure. This can be accomplished by following Results → Surfaces/Contours, which brings up the surfaces and contours window.

The first block contains the Cubes Available, with the Cube Actions button to the right. Under this block is Surfaces Available with the Surface Actions button to the right. There are some boxes below to specify the isovalue for new surfaces of MO, Density, and Laplacian. The final block is Contours Available with the Contour Actions to the right.
The Surfaces and Contours window. Here, the electron density cube was selected and and ESP surface was mapped onto it.

First, pick a type of information to show on the structure through Cube Actions → New Cube. You can plot several different properties. For the example below, I picked the total density as the content for the new cube. The grid options specify how smooth the surface looks. Coarse is fine for quick images, and Medium should be alright for presentations or posters.

You can also use those cubes to plot different information. To do so, follow Surfaces Available → New Mapped Surfaces in the second block. I picked electrostatic potential (ESP) for the example.

A structure of blobs. The left is teal and the right is dark blue. The spectral scale goes from red as negative values to dark blue as positive values.
The electrostatic potential mapped onto the structure.

Cubes can be saved, but surfaces will be recalculated each time.