In TeXForm#
TeXForm parses this entry as a character leaf mapped to U+2662 (WHITE DIAMOND SUIT).
See also#
\backslashbase\lnotbase\negbase
The ♢ symbol (White diamond suit, U+2662), written as \diamondsuit in LaTeX math mode.
TeXForm parses this entry as a character leaf mapped to U+2662 (WHITE DIAMOND SUIT).
\backslash base\lnot base\neg base