Reference tables

Curated quick-reference data for spectrum assignment — IR functional groups, ¹H NMR chemical-shift environments, and visible atomic emission lines (NIST persistent set).

IR functional-group frequencies

27 entries

Group	Range (cm⁻¹)	Intensity	Notes
Alkane C–H stretch	2850–2960	medium	Two or more peaks; sp³ C-H.
Alkene =C–H stretch	3010–3100	medium	Just above 3000 cm⁻¹.
Alkyne ≡C–H stretch	3300	strong	Sharp, characteristic.
Aromatic C–H stretch	3000–3100	medium	Often overlaps with alkene.
Aromatic C–H oop bend	690–900	strong	Substitution pattern fingerprint.
Aromatic C=C ring	1450–1600	variable	Often two or three bands.
Alcohol O–H stretch	3200–3550	strong	Broad when H-bonded.
Carboxylic acid O–H	2500–3300	strong	Very broad shoulder over C-H.
Phenol O–H	3200–3550	variable	Broad, sometimes sharper than alcohol.
Primary amine N–H	3300–3500	medium	Two bands (asym/sym).
Secondary amine N–H	3300–3500	weak	Single band.
Amide N–H	3100–3500	medium	Often two bands.
Aldehyde C=O	1720–1740	strong	Plus 2720/2820 aldehyde C–H doublet.
Ketone C=O	1705–1720	strong	Lowered by conjugation.
Carboxylic acid C=O	1700–1725	strong	Paired with very broad O-H.
Ester C=O	1735–1750	strong	Plus strong C-O at 1150–1300.
Amide C=O	1630–1690	strong	Lower than other C=O.
Anhydride C=O	1750/1820	strong	Two bands (in-phase / out-of-phase).
Acyl chloride C=O	1800	strong	Highest C=O frequency.
C–O stretch (alcohol/ether)	1000–1300	strong	Multiple bands.
Nitrile C≡N	2200–2260	medium	Sharp, distinctive.
Alkyne C≡C	2100–2260	weak	Internal alkynes weaker.
Nitro N=O	1500/1350	strong	Asym + sym pair.
Sulfonate / S=O	1030–1200	strong	Asym + sym for SO₂.
C–Cl	600–800	strong	Fingerprint region.
C–Br	500–650	strong	Fingerprint region.
P=O	1150–1300	strong	Phosphates, phosphonates.

¹H NMR chemical-shift environments

δ (ppm)	Environment	Notes
0.7–1.3	Alkyl CH₃ / CH₂ (sp³)
1.6–2.0	Allylic / α to C=C
2.0–2.6	α to carbonyl (ketone/ester)
2.2–2.9	Benzylic
3.3–4.5	α to O (ether, alcohol)
4.5–6.5	Vinyl =CH
6.5–8.0	Aromatic
9.5–10.0	Aldehyde CHO	Very downfield
10–13	Carboxylic acid OH	Exchangeable

Atomic emission lines (NIST persistent)

140 lines

λ (nm)	Element	Symbol	Assignment	Rel.
213.9	Zinc	Zn		1.00
217.0	Lead	Pb		1.00
232.0	Nickel	Ni		0.70
242.8	Gold	Au		1.00
247.9	Carbon	C	C I	0.70
251.6	Silicon	Si	AAS	1.00
267.6	Gold	Au		0.70
283.3	Lead	Pb		0.85
288.2	Silicon	Si		0.70
307.6	Zinc	Zn		0.55
309.3	Aluminum	Al		1.00
312.3	Gold	Au		0.40
324.8	Copper	Cu	Cu 4p→4s	1.00
327.4	Copper	Cu	Cu 4p→4s	0.95
328.1	Silver	Ag		1.00
336.1	Titanium	Ti	Ti II	0.80
337.1	Nitrogen	N	N₂ 2PG	0.85
338.3	Silver	Ag		0.85
341.5	Nickel	Ni		1.00
352.5	Nickel	Ni		0.85
361.9	Nickel	Ni		0.75
365.4	Titanium	Ti	Ti I	0.90
390.6	Silicon	Si		0.55
391.4	Nitrogen	N	N₂⁺ 1NG	1.00
393.4	Calcium	Ca	Ca II K	1.00
394.4	Aluminum	Al		0.50
396.2	Aluminum	Al		0.55
396.8	Calcium	Ca	Ca II H	0.95
403.1	Manganese	Mn	Mn I	1.00
403.3	Manganese	Mn	Mn I	0.95
403.4	Manganese	Mn	Mn I	0.90
404.4	Potassium	K		0.15
404.6	Iron	Fe	Fe I	0.90
404.7	Mercury	Hg		0.40
405.8	Lead	Pb	Visible	0.60
407.8	Strontium	Sr	Sr II	0.75
410.2	Hydrogen	H	Hδ (n=6→2)	0.22
420.2	Rubidium	Rb		0.25
421.6	Strontium	Sr	Sr II	0.70
422.7	Calcium	Ca	Ca I g	0.60
425.4	Chromium	Cr	Cr I	1.00
427.5	Chromium	Cr	Cr I	0.95
428.9	Chromium	Cr	Cr I	0.90
432.0	Krypton	Kr		0.50
434.0	Hydrogen	H	Hγ (n=5→2)	0.35
435.8	Mercury	Hg	Blue	0.85
438.4	Iron	Fe	Fe I	1.00
447.1	Helium	He		0.45
455.5	Cesium	Cs		0.20
460.3	Lithium	Li		0.30
460.7	Strontium	Sr	Sr I red	1.00
462.4	Xenon	Xe		0.45
469.4	Sulfur	S		0.85
470.3	Magnesium	Mg		0.25
470.5	Bromine	Br		0.60
471.3	Helium	He		0.30
472.2	Zinc	Zn		0.60
478.5	Bromine	Br		0.80
480.7	Xenon	Xe		0.60
481.0	Zinc	Zn		0.50
486.1	Hydrogen	H	Hβ (n=4→2)	0.60
487.2	Strontium	Sr		0.55
488.0	Argon	Ar	Ar II	0.85
489.1	Iron	Fe	Fe I	0.55
491.6	Mercury	Hg		0.20
493.4	Barium	Ba		0.55
498.2	Titanium	Ti	Ti I	1.00
501.6	Helium	He		0.55
510.6	Copper	Cu		0.40
514.5	Argon	Ar	Ar II	1.00
516.5	Carbon	C	Swan band	0.85
516.7	Iron	Fe	Fe I (Mg b region)	0.75
516.7	Magnesium	Mg	Mg b₃	0.90
517.3	Magnesium	Mg	Mg b₂	0.95
518.4	Magnesium	Mg	Mg b₁	1.00
520.6	Chromium	Cr		0.50
520.9	Silver	Ag		0.45
521.8	Copper	Cu		0.35
526.9	Iron	Fe	Fe I	0.60
533.0	Iodine	I	I₂ B-X	1.00
533.2	Bromine	Br		1.00
539.5	Manganese	Mn		0.40
539.7	Iron	Fe	Fe I	0.45
540.1	Neon	Ne		0.30
541.9	Xenon	Xe		0.80
545.4	Sulfur	S		1.00
546.0	Iodine	I	I₂ B-X	0.95
546.1	Mercury	Hg	Green (calibration)	1.00
546.5	Silver	Ag		0.40
553.5	Barium	Ba		1.00
557.0	Krypton	Kr		0.60
557.7	Oxygen	O	O I aurora green	1.00
560.0	Iodine	I	I₂	0.90
568.3	Sodium	Na		0.20
575.0	Iodine	I	I₂	0.85
577.0	Mercury	Hg	Yellow doublet	0.55
579.1	Mercury	Hg		0.55
585.2	Neon	Ne		0.70
587.6	Helium	He	D3 (yellow)	1.00
589.0	Sodium	Na	D2 (3p₃/₂ → 3s)	1.00
589.6	Sodium	Na	D1 (3p₁/₂ → 3s)	0.95
605.8	Krypton	Kr	Std m	1.00
610.4	Lithium	Li		0.45
614.2	Barium	Ba		0.70
614.3	Neon	Ne		0.85
614.8	Bromine	Br		0.55
615.4	Sodium	Na		0.15
616.2	Calcium	Ca		0.25
630.0	Oxygen	O	O I red	0.85
633.4	Neon	Ne		0.90
636.4	Oxygen	O	O I	0.70
640.2	Neon	Ne		1.00
645.6	Krypton	Kr		0.70
650.7	Neon	Ne		0.75
656.3	Hydrogen	H	Hα (n=3→2)	1.00
667.8	Helium	He		0.70
670.8	Lithium	Li	Red 2P→2S	1.00
692.9	Neon	Ne		0.55
696.5	Argon	Ar	Ar I	0.60
703.2	Neon	Ne		0.50
706.5	Helium	He		0.40
706.7	Argon	Ar	Ar I	0.55
725.7	Chlorine	Cl		1.00
746.8	Nitrogen	N	N I	0.55
754.7	Chlorine	Cl		0.75
758.7	Krypton	Kr		0.40
763.5	Argon	Ar	Ar I	0.70
766.5	Potassium	K	K 4p→4s	1.00
769.9	Potassium	K	K 4p→4s	0.95
777.4	Oxygen	O	O I triplet	0.90
780.0	Rubidium	Rb	Rb D₂	1.00
794.8	Rubidium	Rb	Rb D₁	0.95
823.2	Xenon	Xe		0.70
837.6	Chlorine	Cl		0.70
852.1	Cesium	Cs	Cs D₂	1.00
868.3	Nitrogen	N	N I	0.60
881.9	Xenon	Xe		1.00
894.3	Cesium	Cs	Cs D₁	0.95
909.5	Carbon	C	C I	1.00
921.3	Sulfur	S		0.60