The importance of Physical Chemistry is highlighted by variety of outstanding drug withdrawals in recent years. Each of these withdrawals was preceded by severe or fatal adverse effects that had been unrecognized or underappreciated at the time of approval. exploitation the tools of Physical Chemistry, it's potential to spot adverse effects that will be unnoted in irregular trials as a result of those adverse effects square measure uncommon, represent a rise in risk from Associate in Nursing already high baseline (e.g., a rise in risk of infarction or stroke in older patients), occur primarily in patient teams underrepresented in clinical trials (e.g., the old, children, pregnant women), need several months or years to develop, occur primarily with co-administration of specific alternative medication, and/or occur primarily in patients with a particular comorbidity or genotype.
One of the key concepts in classical chemistry is that all chemical compounds can be described as groups of atoms bonded together and chemical reactions can be described as the making and breaking of those bonds. Predicting the properties of chemical compounds from a description of atoms and how they bond is one of the major goals of physical chemistry. To describe the atoms and bonds precisely, it is necessary to know both where the nuclei of the atoms are, and how electrons are distributed around them. Quantum chemistry, a subfield of physical chemistry especially concerned with the application of quantum mechanics to chemical problems, provides tools to determine how strong and what shape bonds are, how nuclei move, and how light can be absorbed or emitted by a chemical compound. Spectroscopy is the related sub-discipline of physical chemistry which is specifically concerned with the interaction of electromagnetic radiation with matter.