Version 9.0.100 (11 June
2015): A draft release of version 9. New features
include faster calculations for larger problems,
Loomis-Wood plots, a wider selection
of units for calculated quantities (for example Angstroms
and Oscillator Strength), a
Vibrational Partition
Function for calculating complete partition functions, a
Check Derivatives
command to assess the accuracy of numerical derivatives, other
tools to assist in fitting and many other smaller improvements and
bug fixes. See the
release notes for a
more detailed list.
.pgo files from older versions will
work without modification in the new version, except in a few
unusual cases, which will give a warning message on loading. A
permanent DOI will be made available for the new version shortly.
Version 8.0.102 (11 December 2013): Minor update to fix
crashes in energy level plots in the Mac version, and some issues
with vibrational calculations. See the
release
notes for a more detailed list of problems fixed; there are
no new features
Version 8.0 (2 December 2013): A significant new
release of
PGOPHER, with the major new feature being the
addition of the calculations involved in a
Force Field Analysis to
PGOPHER.
This allows vibrational frequencies and many other related
quantities including Franck-Condon factors and centrifugal
distortion distortion constants to be calculated from a force
field expressed in terms of bond bending and stretching
coordinates or symmetry coordinates. Fitting the force field to
any reasonable combination of observations is also possible, and
this has been set up so that scaling or otherwise adapting
ab
initio force fields is straightforward. Other significant
new features include:
See the
release notes for a detailed list
of changes, including notes on
upgrading
from previous versions.
Version 7.1 (13 September 2010): Bug fix release - In the
vibrational only mode, linear molecule Franck-Condon factor
calculations for states with non zero vibronic angular momentum
had incorrect intensities, as the degeneracies were not properly
accounted for. A few other
minor issues
have also been fixed.
New in version 7.0 (15 June 2010): Apart
from many minor improvements and bug fixes, several features have
been added at the request of users:
- Interactive adjustment
of
parameters with the mouse.
- Fits to combination differences.
- Uncertainties in calculated line positions can now be
estimated from the results of least squares fitting. This is
enabled by the ShowEstUnc
setting at the top level.
- A separate nuclear spin temperature can be set, Tspin, to model the non
equilibration of nuclear spin states on cooling, such as the
ortho and para states in H2.
- Alternative, simplified line
list format.
- A command line version of PGOPHER is also now
available, with text or Binary
format output. This is particularly suitable for using PGOPHER with other
programs.
- Doppler double peak line shape, as
often found in Fourier transform microwave spectroscopy which
can be used in addition to the standard Gaussian, Lorentzian
and Voigt line shapes.
New in the previous version (6.0):
- A mode for simulating vibrational
structure, including anharmonic and Renner-Teller
effects, starting from a harmonic model. The intensity
calculation includes full multidimensional Franck-Condon
factors taking account of both mode displacements and mixing
between modes (The Dushinsky effect).
- Spectra in the presence of static
external electric and/or magnetic fields can now be
simulated, including plots of energy levels against electric
field suitable for predicting Stark deceleration, focusing and
trapping of molecules.
Introduction
PGOPHER is a
general purpose program for simulating and fitting rotational,
vibrational and electronic spectra. It represents a distillation
of several programs written and used over the past decade or so
within the Bristol
laser group and elsewhere, but is a re-write from scratch
to produce a general purpose and flexible program. PGOPHER will handle
linear molecules and symmetric and asymmetric tops, including
effects due to unpaired electrons and nuclear spin, with a
separate mode for vibrational structure. The program can handle
many sorts of transitions, including Raman, multiphoton and
forbidden transitions. It can simulate multiple species and
states simultaneously, including special effects such as
perturbations and state dependent predissociation. Fitting can
be to line positions, intensities or band contours.
PGOPHER is
designed to be easy to use; it uses a standard graphical user
interface and the program is currently in use for undergraduate
practicals and workshops as well as research work. It has
features to make comparison with, and fitting to, spectra from
various sources easy. In addition to overlaying numerical
spectra it is also possible to overlay pictures from pdf files
and even plate spectra to assist in checking that published
constants are being used correctly.
Most calculations will run on any reasonably modern machine;
larger calculations involving multiple states can benefit from
more memory or processors.