Francium (Fr) X-ray absorption edges

The Fr $L_{3}$ edge is at 15,031 $eV$ . The tables list 24 absorption edges for francium; $L_{1}$ , $L_{2}$ , $L_{3}$ , $M_{1}$ , $M_{2}$ , $M_{3}$ , $M_{4}$ , $M_{5}$ , $N_{1}$ , $N_{2}$ , $N_{3}$ , $N_{4}$ , $N_{5}$ , $N_{6}$ , $N_{7}$ , $O_{1}$ , $O_{2}$ and $O_{3}$ lie between 100 $eV$ and 100 $keV$ , the range the lab can scan.

Atomic number: $Z = 87$
Molar mass: 223 $g / mol$
Edges in the lab range: 18 of 24

Open francium in the lab

Both load francium as a pure sample with the formula $Fr$ . Density is retained from your current settings because these X-ray tables have no density. Enter your sample's density on the Sample page before planning a thickness. To scan another edge, use the links in the table below.

Absorption edges of francium

Energies, jump ratios and fluorescence yields as tabulated by Elam, Ravel and Sieber (2002). Scroll within the table to see every column.
Edge	Energy ( $eV$ )	Jump ratio	Fluorescence yield	In the lab
$K$	101,137	4.481	0.97227	Outside range
$L_{1}$	18,639	1.15688	0.13	ScanHard X-ray
$L_{2}$	17,907	1.4	0.443	ScanHard X-ray
$L_{3}$	15,031	2.443	0.424	ScanHard X-ray
$M_{1}$	4,652	1.04	0.004095	ScanHard X-ray
$M_{2}$	4,327	1.058	0.010812	ScanHard X-ray
$M_{3}$	3,663	1.16056	0.00675	ScanHard X-ray
$M_{4}$	3,136	1.555	0.041325	ScanHard X-ray
$M_{5}$	3,000	3.135	0.039575	ScanHard X-ray
$N_{1}$	1,153	1.017	0.0004225	ScanSoft X-ray
$N_{2}$	980	1.005	0.0003175	ScanSoft X-ray
$N_{3}$	810	1.06	0.0002025	ScanSoft X-ray
$N_{4}$	603	1.02	0.0003275	ScanSoft X-ray
$N_{5}$	577	1.124	0.0003275	ScanSoft X-ray
$N_{6}$	268	1.287	0.000445	ScanSoft X-ray
$N_{7}$	268	1.287	0.000445	ScanSoft X-ray
$O_{1}$	234	1.3	0	ScanSoft X-ray
$O_{2}$	182	1.16	0	ScanSoft X-ray
$O_{3}$	140	1.5	0	ScanSoft X-ray
$O_{4}$	58	1	0	Outside range
$O_{5}$	58	1	0	Outside range
$P_{1}$	24	1	0	Outside range
$P_{2}$	14	1	0	Outside range
$P_{3}$	7	1	0	Outside range

Jump ratio is the photoabsorption just above the edge divided by the photoabsorption just below it. Fluorescence yield is the probability that a core hole in that shell decays by emitting an X-ray. Both are dimensionless. The lab can scan across edges strictly between 100 $eV$ and 100 $keV$ ; other edges are listed for reference. A listed edge with jump ratio 1 has no step for thickness planning.

Transmission, fluorescence or electron yield

$L_{1}$ , $L_{2}$ , $L_{3}$ , $M_{1}$ , $M_{2}$ , $M_{3}$ , $M_{4}$ and $M_{5}$ are hard X-ray edges in the lab's classification (2 $keV$ and above). The sample planner suggests transmission when the edge step is large enough relative to total attenuation. For a small step, as in a dilute absorber, it suggests fluorescence. Concentration alone does not decide the measurement mode.

$N_{1}$ , $N_{2}$ , $N_{3}$ , $N_{4}$ , $N_{5}$ , $N_{6}$ , $N_{7}$ , $O_{1}$ , $O_{2}$ and $O_{3}$ are soft X-ray edges in the lab's classification (below 2 $keV$ ). Transmission generally needs thin films or membranes, so the planner suggests fluorescence or electron yield. The fluorescence yield at $N_{1}$ , $N_{2}$ , $N_{3}$ , $N_{4}$ , $N_{5}$ , $N_{6}$ , $N_{7}$ , $O_{1}$ , $O_{2}$ and $O_{3}$ is below 0.05, where the lab suggests considering total electron yield.

These are planning rules of thumb. Sample thickness, self-absorption and the beamline's energy range and detectors still matter. The lab simulates transmission; it does not simulate fluorescence or electron-yield detector counts.

Values from XrayDB 9.2 (Elam, Ravel and Sieber, 2002), released into the public domain. These isolated-atom tables do not include chemical shifts, XANES or EXAFS fine structure. Methods and data sources