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The Balmer series or Balmer lines in atomic physics, is the designation of one of a set of six named series describing the spectral line emissions of the hydrogen atom. The Balmer series is calculated using the Balmer formula, an empirical equation discovered by Johann Balmer in 1885. The visible spectrum of light from hydrogen displays four wavelengths, 410 nm, 434 nm, 486 nm, and 656 nm, that correspond to emissions of photons by electrons in excited states transitioning to the quantum level described by the principal quantum number ''n'' equals 2.〔C.R. Nave (2006). HyperPhysics: (''Hydrogen Spectrum'' ). Georgia State University. Accessed March 1st, 2008.〕 There are also a number of ultraviolet Balmer lines with wavelengths shorter than 400 nm. == Overview == The Balmer series is characterized by the electron transitioning from ''n'' ≥ 3 to ''n'' = 2, where ''n'' refers to the radial quantum number or principal quantum number of the electron. The transitions are named sequentially by Greek letter: ''n'' = 3 to ''n'' = 2 is called H-α, 4 to 2 is H-β, 5 to 2 is H-γ, and 6 to 2 is H-δ. As the first spectral lines associated with this series are located in the visible part of the electromagnetic spectrum, these lines are historically referred to as "H-alpha", "H-beta", "H-gamma" and so on, where H is the element hydrogen. Although physicists were aware of atomic emissions before 1885, they lacked a tool to accurately predict where the spectral lines should appear. The Balmer equation predicts the four visible absorption/emission lines of hydrogen with high accuracy. Balmer's equation inspired the Rydberg equation as a generalization of it, and this in turn led physicists to find the Lyman, Paschen, and Brackett series which predicted other absorption/emission lines of hydrogen found outside the visible spectrum. The familiar red H-alpha spectral line of hydrogen gas, which is the transition from the shell ''n'' = 3 to the Balmer series shell ''n'' = 2, is one of the conspicuous colours of the universe. It contributes a bright red line to the spectra of emission or ionisation nebula, like the Orion Nebula, which are often H II regions found in star forming regions. In true-colour pictures, these nebula have a distinctly pink colour from the combination of visible Balmer lines that hydrogen emits. Later, it was discovered that when the spectral lines of the hydrogen spectrum are examined at very high resolution, they are found to be closely spaced doublets. This splitting is called fine structure. It was also found that excited electrons could jump to the Balmer series ''n''=2 from orbitals where ''n'' was greater than 6, emitting shades of violet when doing so. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Balmer series」の詳細全文を読む スポンサード リンク
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