Why GC-MS can detect only organic compound, such as carbonhydrate?
(why can't detect inorganic compound such as HfCl4, MoO2Cl2, WF6 ?)
In general, inorganic compounds have higher boiling points than organic compounds. The boiling point of inorganic compounds is quite high. According to the principles of GC-MS, the analyte must be converted to vapor at a temperature approximately below 300 °C. Thus, at operating temperatures, most inorganic compounds cannot be converted to vapor.
GC-Ms detect only organic compounds because it works on compounds that can vapourize below 300 degree C. The most of the inorganic compounds have higher boiling point as more than operating temperature of GC.
The volatility limitations of the gc ms systems would apply to many inorganic compounds. However, the WF6 that you cite in your question has sufficient vapor pressure for a typical gc separation, with a normal bp of 17C. However, WF6 is extremely reactive with water and other molecules that can provide a proton to create HF and a Lewis base to bind to the tungsten , eg, O-H, N-H. In addition, even unsaturated organics and hydro silanes are vulnerable to attack. These reactive residues, generally found in gc column stationary phases are subject to chemical attack with this reagent and result in breakdown of the column resins and bleeding of the analyte on the column. All of molecular examples cited share a relatively high level of reactivity and would provide challenges toward good clean separation on many gc columns.
while not wholly inorganic, there are a number of organometallic compounds that have been characterized by gc-ms techniques.
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