ATOMS uses only 1-byte characters (256 possible characters) for the various types of labels and for file input and output. Most types of file containing structural information use only this type of character encoding, not multi-byte characters such as unicode. As latin characters and arabic numerals for chemical symbols are nearly standard worldwide, this should not cause too much difficulty.
ATOMS previously was restricted to the standard ANSI character set, but this restriction has been removed for the Title and atom labels. Thus it is possible to use fonts with non-latin-based character sets (if simplified to 256 characters), and special fonts such as FEBTechnical to display numeric sub- and superscripts and special characters. Such fonts may be selected through the Font options in these dialog.
In the Title/Axes and Input Atom Data dialogs (Input1 menu) characters for non-ANSI typefaces should be displayed correctly, but at a fixed font size. The list of input atoms in the Atoms dialog (Input1 menu) may not show non-ANSI characters correctly because this list must be written in a fixed-width font (Courier or Monaco).
Note that superscript 1 (character number 185), 2 (178) and 3 (179) are included in the standard ANSI character set and may be displayed in standard latin fonts such as Times, Courier, Monaco, etc.
To insert special characters into the title or atom labels in ATOMS, it may be easiest to generate these in special system-supplied applications or applets, such as the Character Map in Windows or the Character Palette in Macintosh, and cut-and-paste into the text boxes in the ATOMS dialogs. In some operating systems it may be possible to insert characters by number using specific key combinations.
Special fonts with desired characters may be designed, or standard fonts modified, with commercial font-editing tools. The Private Character Editor in recent releases of Windows does not apply to 1-byte characters.
Atom labels may optionally include special roman-numeral superscripts indicating the symmetry-operator number - this is done automatically and should not require any special font as long as the font selected for atom labels contains the standard latin characters used in the roman numerals.