User guide

Where ‘T’ is the temperature at the melting point, ‘DS’ is the change in entropy of melting, and ‘DH’ is the change in
enthalpy of melting.
MR
The Molar Refractivity is estimated by Crippen's fragmentation, and Viswanadhan's fragmentation method. Additional
empirical LogP data appears for selected substances in the report file.
pKa
pKa is the negative log of the acid dissociation constant K
a
. It describes the tendency of compounds or ions to dis-
sociate in solution. It is calculated using the formula:
Empirical pKa data appears for selected substances in the report file.
Note: pKa calculations are available only in Windows version of ChemBioDraw 13.0.
tPSA
Calculation of polar surface area based on fragment contributions.
Property predictions in ChemDraw/Excel
The Properties feature in ChemDraw/Excel lets you view the values of different properties for a given structure. Each
property is calculated using the “best available” method. A list of properties available in ChemDraw/Excel is listed in
the table below. For more information on these properties, see ChemDraw/Excel online help or visit the PerkinElmer
Informatics website .
The properties available include:
B F Melting Point Shape Attribute
Balaban Index Formal Charge Molar refractivity Shape Coefficient
Boiling Point Freezing Point Molecular Formula Sum Of Degrees
C G Molecular Weight Sum of Valence Degrees
Cluster Count Gibbs Free Energy N T
Critical Pressure H Number of rotatable bonds Total connectivity
Critical Temperature Heat of Formation O Topological diameter
Critical Volume Henry's Law Constant Ovality Topological index
Connolly Accessible Area I P Total valence connectivity
Connolly Molecular Surface Area Ideal Gas Thermal Capacity Principal Moments of Inertia (X, Y, Z) V
ChemBioDraw 13.0
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