Using ChemFinder - CambridgeSoft

Dates are always displayed according to the
preferences set in the operating system’s
International control panel.
The following table shows query examples.
Entry Possible hits
Apr 11, 1971 the exact date April 11, 1971
March 31, 1971–
July 1, 1971
any date in the second quarter
of the year 1971
>April 11, 1971 any date after April 11, 1971
Molecular Formula
Searching
Formula searching allows you to search molecular
compositions, exact or in the range that you specify.
The following table shows query examples.
Entry Possible hits
C6H6 compounds with 6 carbons and
6 hydrogen atoms, plus any
number of other elements.
=C6H6 compounds with 6 carbons and
6 hydrogen atoms and no other
elements.
C6N0 compounds with 6 carbons, no
nitrogens, plus any number of
other elements.
C6 N1-3 compounds with 6 carbons and
one to three nitrogen atoms, plus
any number of other elements.
Formula queries consist of element symbols and
element counts or ranges. The following rules apply:
• Symbols may be one or two letters. Symbols
may be in upper or lower case; if there are
ambiguities, the program resolves them
according to rules described in Appendix B.
• Capitalize the symbols properly.
• Insert spaces between symbols.
• Use the Periodic Table to enter formulas. For
more information, see “Using the Periodic
Table” on page 127 and “Appendix B: Formula
Input Rules.”
• Element counts are single integers or ranges
(two integers separated by a hyphen). If a count
is omitted, it is assumed to be 1.
• If the formula query is precede by “=” (=C6H6
for example), then the search requires an exact
formula match, containing no elements other
than those indicated. If there is no “=”, then the
search is a partial match: other elements may be
present in the hits.
• Symbols may be repeated. For example,
“CH3CH3” is interpreted as “C2H6.”
NOTE: Formula searches are completely nonstructural:
CH3CH2OH matches both dimethyl
ether and ethyl alcohol because both
compounds have the same condensed formula:
C2H6O.
• Parentheses may be used to group elements and
apply a count to the entire group. For example,
“(CH2)3” is interpreted as “C3H6.”
• Spaces or non-alphanumeric characters other
than parentheses are ignored.
ChemFinder 8 Chapter 5: Searching • 87
Molecular Formula Searching