Assignment

ω/cm⁻¹ (4-BBP)

ω/cm⁻¹ (K₂4-BBP)

ω/cm⁻¹ (Toluene)

ω/cm⁻¹ (Biphenyl)

Ring

Deformation

ΦC-C

415.6

—

—

406

ΦC-C

465.6

—

—

467

αC-C-C

536.8

—

—

524

αC-C-C

613.8

607.4 (−5)

605

620

αC-C-C

637.2

636.1 (−1)

—

—

C-H Bending

Out-of-plane

γC-H

751.2

—

743

734

γC-H

799.3

791.9 (−7)

790

784

γC-H

851.2

—

—

—

γC-H

993.0

976.7 (−16)

—

983

Ring breathing

999.1

988.9 (−10)

990

1002

C-H Bending

in-plane

βC-H

1026.6

1004.2 (−22)

1033

—

βC-H

1184.4

1172.5 (−12)

1150

1153

βC-H

1193.4

1191.4 (−2)

—

1176

C-C stretching

υ (C-C)

1285.4

1282.5 (−2)

1287

—

υ (C-C)

1513.5

1510.7 (−2)

1510

—

υ (C-C)

1595.4

1589.8 (−6)

1586

1584

υ (C-C)

1609.6

—

1595

1604