% Misc definitions
\newcommand{\kms}{km~s$^{-1}$}
\newcommand\sk[2] {Sk\,{$-#1{^\circ}#2$}}
\newcommand{\tnc}{\,\tablenotemark{c}}
\newcommand{\tnd}{\,\tablenotemark{d}}

% ion definitions
\newcommand{\Ha}{H$\alpha$}      %  Halpha
\newcommand{\HH}{H$_2$}          %  H2
\newcommand{\HI}{\ion{H}{1}}     %  HI
\newcommand{\HII}{\ion{H}{2}}    %  HII
\newcommand{\NaI}{\ion{Na}{1}}   %  NaI
\newcommand{\NII}{\ion{N}{2}}    %  NII
\newcommand{\Lya}{Ly$\alpha$}    %  Lyalpha
\newcommand{\Lyb}{Ly$\beta$}     %  Lybeta
\newcommand{\SII}{\ion{S}{2}}    %  SII
\newcommand{\OVI}{\ion{O}{6}}    %  OVI
\newcommand{\OIII}{\ion{O}{3}}   %  OIII
\newcommand{\OI}{\ion{O}{1}}     %  OI
\newcommand{\CIII}{\ion{C}{3}}   %  CIII
\newcommand{\CII}{\ion{C}{2}}    %  CII
\newcommand{\CI}{\ion{C}{1}}     %  CI
\newcommand{\SiII}{\ion{Si}{2}}  %  SiII
\newcommand{\PII}{\ion{P}{2}}    %  PII
\newcommand{\FeIII}{\ion{Fe}{3}} %  FeIII
\newcommand{\FeII}{\ion{Fe}{2}}  %  FeII
\newcommand{\NV}{\ion{N}{5}}     %  NV
\newcommand{\CIV}{\ion{C}{4}}    %  CIV
\newcommand{\CaII}{\ion{Ca}{2}}  %  CaII