TAPE21 is the general result file of an adf calculation. It is a kf file: Direct-Access, binary, and keyword driven. It contains information about the calculation. You can use it as a fragment file in a subsequent calculation on a bigger molecule, where the current one may be a part, or in an analysis program.
The contents of TAPE21 is keyword-accessible and you may use the KF utilities (see the utilities document) for conversion of TAPE21 from binary to ASCII format and vice versa. This facility is also useful when you intend to use a TAPE21 result file produced on one type of hardware, for a continuation run on a quite different computer: Transform the binary file to ASCII format with the KF utilities on the first machine. Then transport the ASCII file to the other machine, and make a binary out of it again.
Another utility (pkf) can be used to obtain a summary of the contents of TAPE21. The output should be more or less self-documenting: all variables are listed by name, type (integer, real, ..) and size (number of array elements) and grouped in named sections.
The data on TAPE21 is organized in Sections which group together related data. Each section contains a number of variables. Each variable may be an array or a scalar and may be integer, real, logical or character type.
A complete dump of the contents of TAPE21 is obtained with dmpkf. The resulting ASCII file contains for all variables on the file:
A typical case of the contents of TAPE21 obtained by dmpkf operating on the binary TAPE21 file from an optimization run on H2O would be:
| contents of TAPE21 | comment |
| General | name of (first) section |
| file-ident | name of (first) variable in the current section (General) |
| 6 6 3 | characteristics of the data: 6 elements reserved on file for the variable, 6 data elements actually used, 3=integer code for the data type: character |
| TAPE21 | Value of the variable fileident in the section General. |
| General | again: name of the section |
| title | name of the (second) variable |
| 80 80 3 | reserved and used number of data elements (both 80), and the data type code (3: character) |
| Water Geometry Optimization with Internal Coordinates | value |
| (etc.) | (etc.) |
For a description of the various utilities that can be used to process TAPE21 see the ADF Properties and Analysis documents.
Contents of TAPE21
