Formation energy per atom

Property name: Formation energy per atom
Description: The formation energy per atom, (E - sum_i n_i mu_i)/N in electronvolt, with E the total energy of the cell, n_i the number of atoms of element i, mu_i the elemental reservoir chemical potential per atom and N the total number of atoms. The references mu_i are part of the producing analysis and recorded alongside. The reference/zero of the energy scale is method- and code-specific, so values are comparable only within one consistent computational setup. A null value means the quantity is not available or not recorded.
Type: float
Implementation requirements:
- Support: OPTIONAL support in implementations, i.e., MAY be null.

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    "title": "Formation energy per atom",
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            "description": "A unit of energy that representing the kinetic energy acquired by an electron as it accelerates through a 1 volt potential difference in a vacuum using the current, or one of the historical, definitions given in the editions of the International System of Units (SI).\n\nThe electronvolt unit appears in the International System of Units (SI), 1st ed. (1970) defined as \"1 electronvolt is the energy acquired by an electron after traversing a potential difference of 1 V in a vacuum; 1 eV = 1.60219\u00d710\u207b\u00b9\u2079 J approximately.\"\nThis definition makes the unit equal to 1 volt times the value of the elementary charge.\nIn the 2019 redefinition of the SI units the elementary charge is exactly 1.602176634\u00b710\u207b\u00b9\u2079 C, making the electron volt exactly equal to 1.602176634\u00b710\u207b\u00b9\u2079 J.\nThe International System of Units (SI), 9th ed. (2019) accordingly notes the exact relationship with the SI 2019 derived unit joule as \"1 eV = 1.602176634\u00b710\u207b\u00b9\u2079 J\" but retains the definition from 1970 in a footnote.\n\nThe unit is categorized in the International System of Units (SI), 9th ed. (2019) as \"Non-SI units accepted for use with the SI units\".\n\nThis is a generalized definition taken to reference the current, or one of the historical, SI unit definitions.\nThis definition is intended for situations when it is not possible to be more precise, e.g., in contexts where data have been collected that uses different historical SI definitions.",
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    "description": "The formation energy per atom, (E - sum_i n_i mu_i)/N in electronvolt, with E the total energy of the cell, n_i the number of atoms of element i, mu_i the elemental reservoir chemical potential per atom and N the total number of atoms. The references mu_i are part of the producing analysis and recorded alongside.\nThe reference/zero of the energy scale is method- and code-specific, so values are comparable only within one consistent computational setup.\nA null value means the quantity is not available or not recorded."
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Formation energy per atom (property)