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⚛️ Birikmalarning Mössbauer tahlili

δ (izomer siljish) • ΔEQ (kvadrupol) • H (magnit maydon)

6
jami birikma
2
Fe²⁺ kompleks
2
Fe³⁺ kompleks
2
LS (quyi spin)
2
HS (yuqori spin)

📊 δ vs ΔEQ diagrammasi — holatlarni joylashtirish

Har bir nuqta birikmani ifodalaydi. O'q o'qlarini bosib batafsil ma'lumot ko'ring.

-0.200.40.81.21.601234δ (mm/s) — izomer siljishΔE_Q (mm/s)Fe³⁺ LSFe³⁺ HSFe²⁺ LSFe²⁺ HSK₃[Fe(CN)₆]K₄[Fe(CN)₆][Fe(H₂O)₆]²⁺[Fe(H₂O)₆]³⁺[Fe(CO)₅]Fe₃O₄

Fe³⁺ LS

δ < 0.3, ΔEQ < 1

Fe³⁺ HS

δ ≈ 0.3-0.6, ΔEQ < 1

Fe²⁺ LS

δ ≈ 0.2-0.5, ΔEQ < 2

Fe²⁺ HS

δ ≈ 0.9-1.5, ΔEQ > 2

🔍

K₃[Fe(CN)₆]

kaliy geksasiyanoferrat(III)

"Qizil qon tuzi"

⚛️ Dublet
Fe³⁺d⁵ (LS, t₂g⁵)LS (S=1/2)

δ

−0.12

mm/s

ΔEQ

0.38

mm/s

H

0

Tesla

Kuchli maydon ligandlari (CN⁻) → LS holat. t₂g⁵ simmetrik emas → kichik ΔE_Q. Fe³⁺ uchun past δ — yuqori oksidlanish.

→ Batafsil Mössbauer tahlili

K₄[Fe(CN)₆]

kaliy geksasiyanoferrat(II)

"Sariq qon tuzi"

⚛️ Singlet
Fe²⁺d⁶ (LS, t₂g⁶)LS (S=0)

δ

−0.06

mm/s

ΔEQ

0.00

mm/s

H

0

Tesla

t₂g⁶ to'liq to'lgan, sferik simmetrik → ΔE_Q = 0 (singlet). Fe²⁺ bo'lsa ham LS → δ past.

→ Batafsil Mössbauer tahlili

[Fe(H₂O)₆]²⁺

geksaakvatemir(II) ioni

⚛️ Dublet (katta ΔE_Q)
Fe²⁺d⁶ (HS, t₂g⁴ e_g²)HS (S=2)

δ

1.20

mm/s

ΔEQ

3.00

mm/s

H

0

Tesla

Kuchsiz maydon ligandlari (H₂O) → HS holat. t₂g⁴ e_g² asimmetrik → juda katta ΔE_Q. Fe²⁺ HS ning klassik namunasi.

→ Batafsil Mössbauer tahlili

[Fe(H₂O)₆]³⁺

geksaakvatemir(III) ioni

⚛️ Dublet (kichik ΔE_Q)
Fe³⁺d⁵ (HS, t₂g³ e_g²)HS (S=5/2)

δ

0.40

mm/s

ΔEQ

0.20

mm/s

H

0

Tesla

HS Fe³⁺ — d⁵ yarim to'lgan, deyarli sferik simmetrik → kichik ΔE_Q. Fe³⁺ HS ning klassik namunasi.

→ Batafsil Mössbauer tahlili

[Fe(CO)₅]

pentakarboniltemir(0)

⚛️ Singlet
Fe⁰d⁸ (18e⁻)S=0

δ

−0.09

mm/s

ΔEQ

0.00

mm/s

H

0

Tesla

Fe⁰ — nol oksidlanish. CO kuchli π-akseptor → s-elektron zichligi yuqori → δ juda past. Trigonal bipyramidal simmetrik → ΔE_Q = 0.

→ Batafsil Mössbauer tahlili

Fe₃O₄

temir(II,III) oksidi

"Magnetit"

⚛️ Sekstet (2 ta)
Fe²⁺/Fe³⁺Fe³⁺(A) + Fe²⁺(B) + Fe³⁺(B)Aralash

δ

0.67 / 0.27

mm/s

ΔEQ

0.02 / 0.01

mm/s

H

46

Tesla

Aralash valentli — ikki xil Fe mavjud. Tetraedrik (A) Fe³⁺ va oktaedrik (B) Fe²⁺/Fe³⁺. Verwey o'tishi (120 K) — elektron tartib o'zgaradi.

→ Batafsil Mössbauer tahlili

📐 Mössbauer parametrlarini talqin qilish

δ (izomer siljish)

  • ✓ Yuqori δ → past oksidlanish (Fe²⁺)
  • ✓ Past δ → yuqori oksidlanish (Fe³⁺)
  • ✓ HS → LS → δ kamayadi
  • ✓ π-akseptor → δ kamayadi

ΔEQ (kvadrupol)

  • ✓ Katta ΔEQ → past simmetriya
  • ✓ Fe²⁺ HS → ΔEQ ≈ 2-3 mm/s
  • ✓ Fe³⁺ HS → ΔEQ ≈ 0-0.5 mm/s
  • ✓ LS holatlar → kichik ΔEQ

H (magnit maydon)

  • ✓ H = 0 → paramagnit (T > TN)
  • ✓ H > 0 → magnit tartiblangan
  • ✓ Sekstet → 6 chiziq (3:2:1:1:2:3)
  • ✓ Fe₃O₄ → H ≈ 46 T

📋 To'liq solishtirish jadvali

BirikmaIonSpinδΔEQHSpektr
K₃[Fe(CN)₆]Fe³⁺LS (S=1/2)−0.120.380Dublet
K₄[Fe(CN)₆]Fe²⁺LS (S=0)−0.060.000Singlet
[Fe(H₂O)₆]²⁺Fe²⁺HS (S=2)1.203.000Dublet (katta ΔE_Q)
[Fe(H₂O)₆]³⁺Fe³⁺HS (S=5/2)0.400.200Dublet (kichik ΔE_Q)
[Fe(CO)₅]Fe⁰S=0−0.090.000Singlet
Fe₃O₄Fe²⁺/Fe³⁺Aralash0.67 / 0.270.02 / 0.0146Sekstet (2 ta)

✅ Asosiy xulosalar

  1. 6 ta Fe birikma — Fe⁰, Fe²⁺, Fe³⁺ holatlari
  2. δ — oksidlanish darajasi va spin holati ko'rsatkichi
  3. ΔEQ — koordinatsion simmetriya ko'rsatkichi
  4. H — ichki magnit maydon (sekstet uchun)
  5. K₃[Fe(CN)₆] (Fe³⁺ LS) → δ = −0.12, ΔEQ = 0.38, dublet
  6. K₄[Fe(CN)₆] (Fe²⁺ LS) → δ = −0.06, ΔEQ = 0.00, singlet
  7. [Fe(H₂O)₆]²⁺ (Fe²⁺ HS) → δ = 1.20, ΔEQ = 3.00, katta dublet
  8. Fe₃O₄ (aralash valentli) → ikki xil Fe, H = 46 T, sekstet
  9. Mössbauer — Fe komplekslari uchun eng aniq usul
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