On-line Help

Quick start
How it works
Retrieval criteria
Links to numerical databases
Advanced query

Dynamic links to GAPHYOR

Test of retrieval program on various platforms
Recent and coming improvements
Identified problems

The use of this program is presently free, but you can also help us for its development.
Two versions of the database query are now available: Standard Query and Advanced Query. These two versions works the same way. The main difference resides in the presentation of the query form. The Advanced one is presented in a more condensed way with more criteria as bibliographic criteria or chemical elements in a molecule.
If you wish to be informed about future versions, please leave your e-mail address in our mailing list.

Quick start

This program allows to retrieve data (numerical, factual and bibliographic) in atomic and molecular physics and in gaseous chemistry. The retrieval is done in 2 steps, filling and submitting successively 2 forms.

First step: Data Retrieval

On the first step, retrieval is done by submiting the "Data Retrieval" form filled with various criteria such as a molecule, a process, chemical elements...

Second step: Data Selection and Display

As a result of the first step, you get the 2nd form called "Data Selection and Display" which includes:

A reminder of your request
The number of records found for each molecular state matching your request, if you ever defined a molecule in your request.
The total number of found records
New criteria to restrict your request if necessary and configure the display mode.

You can now select and display the Data:

with or without a further selection
in full decoded mode or in a condensed way in a Postscript file.

How it works

Retrievals are done with various criteria which can be used independently or together:

In the first step:

One or two reactants
Section
Process or chemical property
Additional information: type of data, energy levels, clusters, ...
Numerical values and new data
Number of chemical elements involved in the reaction: from 1 to 4
Chemical elements actually identified in the reaction
Bibliographic criteria (Advanced Query)

In the second step:

One specific "reactant" from the displayed list of reactant states satisfying your request if you ever specified a reactant in the first step
The most recent data
The mode of information display:
- in fully decoded mode, sorted by year, convenient for a small number of data
- in a postscript file, producing the same format as in GAPHYOR HANDBOOK, for a large number of data

What is a criterion
Every retrieval criterion is shown in the retrieval page by the icon . By clicking on this icon, one obtains informations related to this criterion. A criterion can be:

A value to be typed with the keyboard as for the "formula" and the ionisation state of a molecule. In this case:
- A syntax verification is done
- A list of possible values is obtained by the hypertext link preceding the criterion to be filled
- Fields are not case sensitive
A value or more selected from a proposed list
Radio buttons to check

What happens after submitting the first form

Once submitted the first form, depending on how you filled it and the number of found data, a second form (step 2) is displayed which includes :

A reminder of your query
The list of molecular states satisfying your request
If you specified a molecule in step 1, you get the list of molecular states which satisfy your query with the number of corresponding data for every state. If this number is less than 1000, you can select this state as a new criterion to get data (radio button). Then the search will be done only for this state, coupled with other criteria selected in step 1 (elements, process, additional information, ...). Don't forget to switch radio button (see further) to get data from the selected molecule and not from the whole set.
The total number of records obtained
How to get data
To get data, different cases may occur, depending upon the total number of found records and whether you specified or not a molecule in your query:
1. No records are found: you have to modify your query going back to the previous page or, sorry, nothing matches your search.
2. You specified a molecule in the first step (pass 1):
  - The total number of records is less than 1000 ; you can get data:
    - from the whole set of states (default case)
    - from the selected state. Don't forget to switch the radio button in this case.
  - The total number of records is larger than 1000, you can get data only from a selected state, no other choice is possible.
3. You did not specify a molecule in the first form (step 1). If the total number of records does not exceed 1000, then you can get data up to the 300 more recent ones. If the total number is larger than 1000, then you have to make your request more accurate or to use the facilities described in the note below.

Display mode
You can display data in 2 differents ways, depending upon the total number of records obtained:

On screen, sorted by year in a fully decoded way (default mode). Display is then limited to the 50 most recent data.
In a postscript file, sorted and presented in the same way as in GAPHYOR HANDBOOK, in a condensed way: a table, with one data per line. This file is afterward transferable by FTP. As screen display is limited to 50, don't forget to switch the radio button if you got more data. Postscript files are limited to 300 records

Notes:

Displaying up to 50 records on screen and 300 in a postscript file is arbitrary. If this gives you particular problems, please mail us, we can change this in a future version.
Sorting of data is limited to 1000 records due to the system performance. If you wish to get larger sets of Data, you can ask for an "Expert's Report", or subscribe to an un-limited access (see Fees). In both cases you should then specify your requests by e-mail: we shall proceed to special retrievals, and we shall send you the results as booklets, printed in the GAPHYOR UPDATE format.

Retrieval criteria

Reactant: Molecule or atom

Actually, 2 molecules or more exactly 2 reactants can be defined. Those reactants can be either:

An atom or a molecule in any ground, ionized and/or excited state: "standard reactant".
An elementary particule like a electron, a photon or a neutron.
A field: magnetic, electric or electromagnetic.
A special reactant to describe:
- A surface or an adsorbed molecule.
- A cluster.
- An isoelectronic series.

7 fields appear on the same line (one line per reactant) to specify an atom or a molecule or an other reactant:

Field 1: the "formula"

The "formula" is the chemical formula of an atom or a molecule, without specifying its ionisation or excitation state, as for example C1O2 for carbon di-oxyde. The "formula" can also define a particle, a field or a special reactant, as for example emf for an electro-magnetic field or (Cu)s for a cupper surface.

For an atom or a molecule enumerate every atom of the molecule even for 1. This is to distinguish for example, as the acquisition is case insensitive, CO (C1O1 = carbon monoxyde), from Co (CO1 = cobalt atom).
For particles or fields do not enumerate, example: emf.
For electronic collisions or photonic collisions don't specify the electron or photon as molecule (except for special ones such as a polarized electron), better specify the section.
For special reactants 2 possibilities are available:
1. Just proceed as for a "standard" reactant and specify the type of reactant in field 6: surface, iso-electronic series, ...
2. Use a plain code:
  - (Na1Cl1)s for a surface of NaCl.
  - (O1)a for an adsorbed atom or molecule.
  - Aa(Li) for the iso-electronic series of Lithium.
  - for the clusters (motif and kernel) use the standard notation, using field 6 as above.
  In this case (plain code), the field 6 doesn't have to be filled.
Warning: there are 2 types of surface:
- stoechiometric: (Cu1S1)s
- alloy: (Al-Cu)s where Aluminium is the prevailing element.
Therefore, for the system, if (Cu1S1)s is equivalent to (S1Cu1)s, (Al-Cu)s is different of (Cu-Al)s.

Field 2: ionization state

0 or blank for ground state. This is the default value.
"n"+ where "n" can take the value from 1 to 99.
"n"- where "n" can take the value from 1 to 20.
N+ to select any positive ion or molecule: ionization from + to 99+.
N- to select any negative ion or molecule: ionization from - to 20-.
all to select atom or molecule disregarding its ionization state.

Fields 3 to 5: excitation state

3 fields are available to specify the excitation state of an atom or a molecule:

Field 3 for "strong" excitation:
- * electronic excitation
- V vibrational excitation
- 0 none, default value
Field 4 for "weak" excitation:
- r rotational excitation
- n isotopic effect
- p polarized reactant
- by default any of this value is taken into account. It means that for "SiF4 *", molecule "SiF4 *r" or "SiF4 *nr" will satisfy the criteria.
Field 5: for "special" excitation:
- m metastable state
- y Rydberg state
- z collective excitation
- by default none

Field 6: type of reactant

Select here the type of reactant you want, by default search is done on standard reactant, clusters and adsorbed molecule:

surface and adsorbed molecule
cluster: motif or kernel
iso-electronic series

Field 7: Initial or Final State

This criteria is to decide whether you want the search to be done on the initial state or on the final state of the reaction.

Additional fields: Advanced Query

Chemical elements
Chemical families
Number of chemical elements

More information on reactant such as the meaning of various values.

Section

The Database is divided into five sections each covering a domain of physics, chemical physics and plasma physics. If necessary, select only the field of interest.

Process

Find in the process list the process you are looking for. Then copy it into the field (lower or upper case). In the advanced query, 1 to 4 processes can be selected.

Additional informations

Values and meanings
If the multiple-choice selection table is unreadable or incomplete: please better try an other browser.

4 kinds of additional information are available:

Data type: cross-sections, reaction rates, ...
Nature: experimental data, review paper, ...
Energy range.
Special data: clusters, surfaces, isoelectronic series.

These 4 types are presented in 4 columns where:

Selecting values from different columns produces a "logic AND":

    Selecting E and K to get experimental data on reaction
rate constants.

In the first 2 columns, selecting several values in the same column will produces a "logic OR":
```
    Selecting E and R to get experimental data or data from
review papers.
```
For energy range (info: L, J and H), no multiple choice is available: historically there were some fluctuations in the coding procedure for this field. Then, using one or several values in this column, could cause lacks. Finally it is usually better not select any value, unless to restrict your query.
In the last column (special data) the choice is also single.

Note: to select a second element in the same column, select it with the "control" key down (Mac Intosh and PC systems). Proceed the same way to "unselect" this element.

Numerical values and new data

Numerical values select only data with numerical values on line. Numerical values can be a radiative lifetime, a reaction rate, cross sections, ... For example, to summarily describe a cross section or a potential curve, the maximum value can be given within the range of energy.
New data are the ones introduced in the database during the current year.

Check radio button to select your desired choice. By default no selection is done (all data).

Number of chemical elements

The physical and chemical systems described in the Database can involve from 1 to 4 chemical elements, not taking into accounts the "elements" of family PA:

transition probability of He*               1 chemical element
collisions between electrons and CO2        2 chemical elements
collisions between protons (H+) and CO2     3 chemical elements
viscosity of a H3N + CO2 mixture            4 chemical elements

Chemical elements

One can select from 1 to 4 chemical elements in the periodic chart (as long as one does not outpass the number specified by the preceding criterion).

In Gaphyor, some particles and fields are considered as chemical reactants (elements of family PA). They are not taken into account for the evaluation of the number of elements, but they can be selected ; these pseudo-elements are:

ef     electric field
bf     magnetic field
emf    electromagnetic field
mu     mu meson
nn     neutron
eo     partially ionized
ei     fully (or strongly) ionized gas

Note that there are other particles as for instance electrons and photons. However, since they are not specific, it is usually not advisable to select them, because it makes the retrieval more complex without any significant improvement of the results.

Bibliographic criteria: Advanced Query

Author
Journal
Year

Last modification, February, 20, 2001