Suggestions for chemarr

The following packages have something in common with the package chemarr. The packages are ordered in decreasing similarity.

Package chemarrow: Arrows for use in chemistry
Package centernot: Centred \not command
Package setouterhbox: Set hbox in outer horizontal mode
Package ghsystem: Globally harmonised system of chemical (etc) naming
Package colonequals: Colon equals symbols
Package achemso: Support for American Chemical Society journal submissions
Package hypgotoe: Links to embedded files
Package chemsym: Macros for typing chemical symbols
Package xymtex: Typesetting chemical structures
Package carbohydrates: Carbohydrate molecules with chemfig
Package modiagram: Drawing molecular orbital diagrams
Package chemnum: A method for numbering chemical compounds
Package chemgreek: Upright Greek letters in chemistry
Package eolgrab: Catch arguments delimited by end of line
Package flags: Setting and clearing of flags in bit fields
Package enparen: Consistent nested brackets
Package bmpsize: Extract size and resolution data from bitmap files
Package hyphsubst: Substitute hyphenation patterns
Package engord: Converts numbers to English ordinal numbers
Package hypbmsec: Hypertext bookmarks in sectioning commands
Package fibnum: Generate Fibonacci numbers
Package iflang: Expandable checks for the current language
Package resizegather: Automatically resize overly large equations
Package rotchiffre: Perform simple rotation cyphers
Package stampinclude: Inclusion based on .aux file date stamps
Package stackrel: Enhancement to the \stackrel command
Package thepdfnumber: Print PDF numbers with minimal digits
Package twoopt: Definitions with two optional arguments
Package settobox: Assigning dimensions of a box to a length register
Package ifdraft: Detect draft and final class options
Package pdfcolparcolumns: Fix colour problems in package parcolumns