cht

CHT(1)                      General Commands Manual                     CHT(1)



NAME
       cht - chemtool drawings analyzer

SYNOPSIS
       cht [-options] filename.cht

DESCRIPTION
       cht is a commandline tool to derive the sum formula and molecular mass
       of the molecule depicted in a chemtool drawing file.  It is also
       available from within chemtool to calculate these data for the current
       structure or a marked fragment of it.

       cht currently recognizes the element symbols  C, H, O, N, P, S, Si, B,
       Br, Cl, F, I, Al, As, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge,
       In, K, Li, Mg, Mn, Na, Ni, Pb, Rb, Sb, Sc, Se, Sn, Sr, Te, Ti, Tl, V,
       Zn (that is, all main group elements except the noble gases, and the
       first row of transition metals) and the abbreviations Ac, Ade, Bn, Bu,
       iBu, tBu, Bz, BOC, Cyt, CE, DBAM, DMAM, DMTr, Et, Gua, Me, Ms, MOC,
       MOM, MMTr, Ph, Pr, iPr, Tf, Thy, Tol, Tr, Ts, TBDMS, TBDPS, TMS, TMTr,
       Ura, Z.
       It can handle two levels of parentheses; e.g. P[OCH(CH_3)_2]_3.
       When cht detects any duplicate (overlapping) bonds in the drawing file,
       it will prepend an exclamation mark to the calculated (and likely
       wrong) sum formula.

OPTIONS
       Cht understands the following options.

       -h , --help
              Displays brief help and list of options.

       -e , --exact
              Calculate exact mass for MS.

       -v , --verbose
              Be verbose.

       -d , --debug
              Be extremely verbose.

BUGS
       Cht can misinterpret molecules that contain the 'aromatic ring' symbol,
       as it uses a fixed search radius to identify the aromatic system that
       it denotes.  It also does not handle the 'partial double bond', so you
       should avoid these two in drawings that you intend to use with cht.

       A label that is offset from the corresponding bond end by more than
       five pixels is not recognized, so that the default CH2 or CH3 group
       enters the calculation in its place.

       In general, one should check the plausibility of the generated sum
       formula wherever possible.

SEE ALSO
       chemtool (1).

AUTHOR
       Radek Liboska



                                 June 17, 2001                          CHT(1)