psi3 software package provides Quantum Chemical Program Suite, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install psi3
psi3 is installed in your system.
Make ensure the psi3 package were installed using the commands given below,
$ sudo dpkg-query -l | grep psi3 *
You will get with psi3 package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Science |
| Package | psi3 |
| Version | 3.4.0-5 |
| Description | Quantum Chemical Program Suite |
| Sub Section | Science |