Hello

I've been studying PPCHTEX these days, it's very powerful, and I cannot
control it well. I just wrote a chemical struture like:

================================
\startchemical
  [size=small,scale=small,width=fit,height=fit,frame=on]
  \chemical[SIX,SB13456,DB2,Z]
    [C,C,C,C,C,C]

\chemical[PB:Z1,ONE,Z0,SB18,Z8,MOV1,ONE,DB1,SB7,Z07,MOV1,ONE,SB13,Z03,MOV1,ONE,SB1,DB7,Z017,PE]
    [C,H,C,H,C,H,C,CH_3,O]
  \chemical[PB:Z2,ONE,Z0,SB1,Z1,PE]
    [C,CH_3]
  \chemical[PB:Z3,ONE,Z0,SB3,Z3,PE]
    [C,H]
  \chemical[PB:Z4,ONE,Z0,SB45,Z45,PE]
    [C,H,H]
  \chemical[PB:Z5,ONE,Z0,SB56,Z56,PE]
    [C,CH_3,H]
  \chemical[PB:Z6,SIX,Z3,SB23,Z24,PE]
    [C,CH_3,CH_3]
\stopchemical
================================

only the carbon-ring is in the frame, I think maybe PB:..,PE pair does not
change the size of the picture. I know I can use like
================================
\startchemical
  [size=small,scale=small,width=9000,height=5000,left=3000]
================================
to specify the size, but I need to try several times to get a correct
version. Is there any parameter that do this staff automatically?

Thanks


-- 
Sincerely yours,
Chen
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          Zhi-chu Chen | Shanghai Synchrotron Radiation Facility
         No. 2019 | Jialuo Rd. | Jiading | Shanghai | P.R. China
             tel: 086 21 5955 3405 | zhichu.chen.googlepages.com
                                               | www.sinap.ac.cn
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