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Calculated Second moments
The second moment Paais defined as:
Where mi is the mass of the ith atom,
and ai is the distance of that atom from the a-axis.
The second moments are related to the moments of inertia by
Paa = (Ibb + Icc - Iaa)/2
Please enter the chemical formula
Rules for chemical formula
Enter a sequence of element symbols followed by numbers
to specify the amounts of desired elements (e.g., C6H6).
Elements may be in any order.
If only one of a given atom is desired, you may omit
the number after the element symbol.
Parentheses may be used to group atoms.
Multiple specifications for an atom will be added.
This means that CH3(CH2)4CH3 will be
treated the same as C6H14.
A comma delimited list of several species may be entered.
Ions are indicated by placing + or - at the end of the formula (CH3+, BF4-, CO3--)
Species in the CCCBDB
Mostly atoms with atomic number less than than 36 (Krypton), except for most of the transition metals.
See section I.B.1 for a periodic table view.
Six or fewer heavy atoms and twenty or fewer total atoms.
Exception:
Versions 8 and higher have a few substituted benzenes with more than six heavy atoms.
Versions 12 and higher have bromine-containing molecules.