Hund’s rules for ordering of terms
E879731
Hund’s rules for ordering of terms are empirical guidelines in atomic spectroscopy that predict the relative energies and ground-state term of an atom by specifying how electron spins and orbital angular momenta combine under LS (Russell–Saunders) coupling.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Hund’s rules | 1 |
| Hund’s rules for ordering of terms canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T10672091 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Hund’s rules for ordering of terms Context triple: [Russell–Saunders coupling, governs, Hund’s rules for ordering of terms]
-
A.
Russell–Saunders coupling
Russell–Saunders coupling is an atomic physics scheme that describes how individual electron orbital and spin angular momenta combine to determine the total angular momentum of an atom, especially in light atoms.
-
B.
Herzberg–Teller approximation
The Herzberg–Teller approximation is a refinement in molecular spectroscopy that accounts for vibronic coupling by allowing electronic transition dipole moments to depend on nuclear coordinates, explaining intensity in otherwise forbidden transitions.
-
C.
Slater-type orbital basis sets
Slater-type orbital basis sets are mathematical functions used in quantum chemistry to approximate atomic orbitals with realistic radial behavior, particularly in early and conceptual implementations of electronic structure methods.
-
D.
Sommerfeld quantization rules
Sommerfeld quantization rules are an early quantum theory refinement of Bohr’s model that quantize electron motion in elliptical orbits using action integrals, helping to explain fine-structure details in atomic spectra.
-
E.
Rydberg–Ritz combination principle
The Rydberg–Ritz combination principle is a rule in atomic spectroscopy stating that the frequencies (or wavenumbers) of spectral lines can be expressed as differences between terms in a series, enabling systematic prediction and classification of atomic spectra.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Hund’s rules for ordering of terms Target entity description: Hund’s rules for ordering of terms are empirical guidelines in atomic spectroscopy that predict the relative energies and ground-state term of an atom by specifying how electron spins and orbital angular momenta combine under LS (Russell–Saunders) coupling.
-
A.
Russell–Saunders coupling
Russell–Saunders coupling is an atomic physics scheme that describes how individual electron orbital and spin angular momenta combine to determine the total angular momentum of an atom, especially in light atoms.
-
B.
Herzberg–Teller approximation
The Herzberg–Teller approximation is a refinement in molecular spectroscopy that accounts for vibronic coupling by allowing electronic transition dipole moments to depend on nuclear coordinates, explaining intensity in otherwise forbidden transitions.
-
C.
Slater-type orbital basis sets
Slater-type orbital basis sets are mathematical functions used in quantum chemistry to approximate atomic orbitals with realistic radial behavior, particularly in early and conceptual implementations of electronic structure methods.
-
D.
Sommerfeld quantization rules
Sommerfeld quantization rules are an early quantum theory refinement of Bohr’s model that quantize electron motion in elliptical orbits using action integrals, helping to explain fine-structure details in atomic spectra.
-
E.
Rydberg–Ritz combination principle
The Rydberg–Ritz combination principle is a rule in atomic spectroscopy stating that the frequencies (or wavenumbers) of spectral lines can be expressed as differences between terms in a series, enabling systematic prediction and classification of atomic spectra.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
empirical rule
ⓘ
rule in atomic physics ⓘ spectroscopic rule ⓘ |
| alsoKnownAs | Hund’s rules NERFINISHED ⓘ |
| appliesTo |
LS coupling
ⓘ
light atoms ⓘ many-electron atoms ⓘ open-shell electron configurations ⓘ |
| approximate | true energy ordering of atomic terms ⓘ |
| assumes |
LS coupling is a good approximation
ⓘ
weak spin–orbit coupling ⓘ |
| basedOn | Russell–Saunders coupling NERFINISHED ⓘ |
| category | selection and ordering rules in spectroscopy ⓘ |
| characterizes |
combination of electron spins
ⓘ
combination of orbital angular momenta ⓘ |
| component |
Hund’s first rule
NERFINISHED
ⓘ
Hund’s second rule NERFINISHED ⓘ Hund’s third rule NERFINISHED ⓘ |
| contrastedWith | jj coupling scheme ⓘ |
| dependsOn |
less-than-half-filled subshells
ⓘ
more-than-half-filled subshells ⓘ |
| describes |
ground-state term of an atom
ⓘ
ordering of atomic term symbols ⓘ relative energies of atomic terms ⓘ |
| field |
atomic physics
ⓘ
atomic spectroscopy ⓘ |
| influences |
fine-structure splitting patterns
ⓘ
magnetic properties of atoms ⓘ |
| involves |
electron–electron repulsion
ⓘ
spin–orbit interaction ⓘ |
| namedAfter | Friedrich Hund NERFINISHED ⓘ |
| originatedIn | early 20th century ⓘ |
| predicts |
for a given multiplicity, term with largest L lies lowest
ⓘ
ordering of J levels within a term ⓘ term with maximum multiplicity has lowest energy ⓘ |
| relatedTo | term symbol notation 2S+1LJ ⓘ |
| relatesTo |
total angular momentum quantum number J
ⓘ
total orbital angular momentum quantum number L ⓘ total spin quantum number S ⓘ |
| states |
for less-than-half-filled subshells, lowest J has lowest energy
ⓘ
for more-than-half-filled subshells, highest J has lowest energy ⓘ |
| usedFor |
assignment of spectroscopic terms
ⓘ
qualitative prediction of atomic spectra ⓘ |
| usedIn |
construction of energy level diagrams
ⓘ
determination of atomic ground states ⓘ interpretation of atomic spectra ⓘ |
| validWhen | electron–electron interactions dominate over spin–orbit coupling ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Hund’s rules for ordering of terms Description of subject: Hund’s rules for ordering of terms are empirical guidelines in atomic spectroscopy that predict the relative energies and ground-state term of an atom by specifying how electron spins and orbital angular momenta combine under LS (Russell–Saunders) coupling.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Hund’s rules