Aromatic Amines

Vibrational Mode Assignment

SERS Spectra Wavenumber (cm⁻¹)

Theo.

Expt.

Aniline

NH₂ wag

C₂NC₆ s-str

R br {NH₂ wag}

RC_2,3C_5,6H ip s-sc {NH₂ wag}/

RC_3,4C_5,6H ip s-sc/RC_2,3C_5,6H ip s-sc

# C N str RC_2,3C_5,6H s-rk NH₂ wag

RC_1,2C_4,5H s-str/

RC_2,3C_5,6 H s-str NH₂ sc /NH₂ sc

1046

812

1015

1048/1185/1201

1235

1643/1642/1651

996

824

960

1025/1144/1172

1214

1558/1571/1592

2-Nitroaniline

NH₂ wag

NO₂ sc R br C NH₂ str

C_3,4C₅,₆H ip s-sc NH₂ rk/C_3,4C_5,6H ip as-sc NH₂ rk/ C_3,4C_5,6H ip s-sc NH₂ rk

C NO₂ str C NH₂ str RC₂C₃ str NH₂ sc

RC_3,4C_5,6 H ip s-rk NH₂ rk

RC_3,4C_5,6 H ip s-rk NH₂ rk C NO₂ str

RC₁,₂C₃,₄C₅,₆ s-str NH₂ rk

RC₁,₂C₄,₅ s-str NH₂ sc/NH₂ sc/

RC₂,₃C₅,₆ s-str C NH₂ str NH₂ sc

263

836

1070/1186/1195

1270

1309

1359

1397

1600/1624/1662

OSR*

817

1048/1179/1195

1255

1285

1349

1368

1521/1608/1571

3-Nitroaniline

NH₂ wag

NO₂ sc R br C NH₂ str

RC_2,4,6 str (R br)

NH₂ rk RC₄C₆H sc /NH₂ rk RC₂,₄,₆H as-sc/

RC_4,5,6H as-sc

C NH₂ str RC₂C₄H ip s-rk

# C NO₂ str{RC₂,_4,6H ip s-rk C NH₂ str}

RC_1,2C_4,5 s-str NH₂ rk/NH₂ sc RC_2,3C_5,6 s-str/

NH₂ sc RC_2,3C_5,6 s-str

464

839

1009

1077/1128/1194

1299

1309

1615/1669/1652

483

808

996

1043/1162/1216

1270

1345

1612/1622/1646

4-Nitroaniline

NH₂ wag

NO₂ sc R br

RC₂,₃C_5,6 H as-sc NH₂ rk /RC_2,3C₅,₆H as-sc NH₂ rk/

RC_2,3C₄,₅H ip s-sc

C NH₂ str RC_2,3C_5,6 s-rk

# C NO₂ str C NH₂ str RC₂C₆ H sc

RC₁,₂C₃,₄C₅,₆ s-str NH₂ rk

NO₂ as-str RC_1,2C_4,5 s-str/NH₂ sc RC_2,3C_5,6 s-str/

NH₂ sc

243

878

1049/1154/1207

1347

1303

1379

1617/1643/1665

OSR*

859

1045/1148/1175

1316

1332

1379

1572/1596/1626

Nitrobenzene

NO₂ sc R br C N str

RC_2,4,6 str (R br)

RC_2,3C_5,6 H ip s-sc /RC_2,3C_4,5 H as-sc/

RC_2,3C_5,6 H ip s-sc

# C NO₂ str RC_2,3C₅,₆ H s-sc

# NO₂ as-str RC_3,4,C₄,₅ as str/RC₂,₃C_5,6 s-str/

NO₂ as-str RC_1,2C_4,5 s-str

877

1017

1042/1188/1199

1305

1552/1627/1643

860

1010

1023/1151/1177

1339

1547/1590/1616