The theoretical value of the magnetic susceptibility of an organic molecule depends on several factors, including the molecular structure, the presence of unpaired electrons, and the applied magnetic field. Magnetic susceptibility is a measure of how a material responds to an external magnetic field, and it can be either positive paramagnetic or negative diamagnetic .In organic molecules, the primary factors that contribute to magnetic susceptibility are:1. Molecular structure: The arrangement of atoms and bonds within the molecule can influence its magnetic properties. For example, molecules with conjugated -systems or aromatic rings may exhibit different magnetic susceptibilities compared to their non-conjugated counterparts.2. Presence of unpaired electrons: Organic molecules with unpaired electrons, such as radicals or molecules with transition metal ions, can exhibit paramagnetic behavior due to the presence of these unpaired electrons. In contrast, molecules with all paired electrons will generally be diamagnetic.3. Applied magnetic field: The strength of the applied magnetic field can affect the magnetic susceptibility of the molecule. In general, stronger magnetic fields can lead to larger magnetic susceptibilities.4. Temperature: The magnetic susceptibility of a molecule can also be influenced by temperature, as the thermal energy can affect the alignment of the unpaired electrons within the molecule.To calculate the theoretical value of the magnetic susceptibility for a specific organic molecule, one can use quantum chemical calculations or semi-empirical methods. These computational approaches take into account the molecular structure and electronic configuration of the molecule to predict its magnetic properties. However, it is important to note that these calculations can be complex and may require specialized software and expertise to perform accurately.