The article by Linus Pauling and Charles D. Coryell investigates the magnetic properties and structure of hemoglobin, oxyhemoglobin, and carbonmonoxyhemoglobin. They found that oxyhemoglobin and carbonmonoxyhemoglobin contain no unpaired electrons, while ferrohemoglobin (hemoglobin itself) contains four unpaired electrons per heme. The study also revises the nomenclature of hemoglobin-related substances to make them more descriptive. The magnetic measurements show that carbonmonoxyhemoglobin and oxyhemoglobin have zero magnetic moments, indicating covalent bonds between the iron atom and other atoms. In contrast, ferrohemoglobin has a pronounced paramagnetic contribution, suggesting ionic bonds. The heme-heme interaction is proposed to stabilize parallel configurations of the magnetic moments. The structural changes in hemoglobin upon oxygen or carbon monoxide binding are discussed, highlighting the shift from ionic to covalent bonds. The findings provide insights into the characteristic properties of hemoglobin, such as its affinity for oxygen and carbon monoxide.The article by Linus Pauling and Charles D. Coryell investigates the magnetic properties and structure of hemoglobin, oxyhemoglobin, and carbonmonoxyhemoglobin. They found that oxyhemoglobin and carbonmonoxyhemoglobin contain no unpaired electrons, while ferrohemoglobin (hemoglobin itself) contains four unpaired electrons per heme. The study also revises the nomenclature of hemoglobin-related substances to make them more descriptive. The magnetic measurements show that carbonmonoxyhemoglobin and oxyhemoglobin have zero magnetic moments, indicating covalent bonds between the iron atom and other atoms. In contrast, ferrohemoglobin has a pronounced paramagnetic contribution, suggesting ionic bonds. The heme-heme interaction is proposed to stabilize parallel configurations of the magnetic moments. The structural changes in hemoglobin upon oxygen or carbon monoxide binding are discussed, highlighting the shift from ionic to covalent bonds. The findings provide insights into the characteristic properties of hemoglobin, such as its affinity for oxygen and carbon monoxide.