SCIENTIFIC ABSTRACT VALIYEV, K.A. - VALKA, O.

Document Type: 
Document Number (FOIA) /ESDN (CREST): 
CIA-RDP86-00513R001858510005-8
Release Decision: 
RIF
Original Classification: 
S
Document Page Count: 
100
Document Creation Date: 
November 2, 2016
Document Release Date: 
August 31, 2001
Sequence Number: 
5
Case Number: 
Publication Date: 
December 31, 1967
Content Type: 
SCIENTIFIC ABSTRACT
File: 
AttachmentSize
PDF icon CIA-RDP86-00513R001858510005-8.pdf3.61 MB
Body: 
28756 9/056J61/041/003/009/020 Theory of spin-lattios relaxation... B125/BI02 terms in the series expansion of the spin energy, which are linear with respect to QJ, The terms in the expansion of %(2), which are quadratic with respeatto Qp excite a more efficient relaxation. rndepeniently of the present authors, r. V. Aleksandrov and 0. M. Zhidomirov arrived at the same conclusion (ZhETY, ~Ll, 127, 1961). The relaxation-transition probability between sublevels of the spin energy is calculated from the perturbation-theoretical formula w ~;-2 Z f 1/2), another relaxation -1 2 02 2 mechanism is possible, which leads to Ti ~alh (ttj/2kT)-rr/('+ M 'MITP. 2+ 1 The reeonance-line vi th of Cu ions in aqueous solution: The orbital Card 5/7 28756 S/056 '61/041/003/009/020 ,Theory of spin-lattice relaxation... B1257B102 levels are described bythe wave functions -Y2 + 'F -Ta - ( -2)/rZ ' 'Pb - V.' 'Po - (12 - V-2)/F21 Yd - (VI + V-1 )/ F21 'f6 - OYI -:1-1 )/f 2. A 104 and 6 '103cm7~ The width of the resonance line observed during the transitions at M - -1/2 - a, M - + 1/2 is due to relaxation transitions etween the orbital sublevels a and b which are excited tinder the action of WM alone (without participation of the interaction ArS ). The direct transitions a-b are much more probable than transitions with spin re-orientation. The matrix element of a direct transition reads 941-1b =a(Q:7-q,,)+bQsQs+cQ6Q,; a (A, ~5- A.). b=- 18 A, 375 A, 1!5 IL3 As, (17i 8 ( WO 8 A, eea?R-5, A, et'~74R-I, a 3P 2/21. and the probabilities of the transitions a-*b reid 2 [a2 (--T -T 'j -3 -7 2--772 -6/2kT w + Ib' - 0 e (20)- a,b 5155 Q6~66) Q2 Q3f23 + Card 6/7 28756 S/056J61/041/003/009/020 Theory of spin-lattice relaxation... 3125/B102 The temperature dependence of (20) is given by V -exp(-6/2kT) a th2 (A W/2kT)Xio where X jexp(-E/RT)j the parameter E a,b i j has the significance of a "viscosity barrier" of ~he liquid. The 1.8-fold broadening of the line in the same temperature range, obser7ed by Kozyrev, is close to the calculated value. There are 1 figure and 12 references: 5 Soviet and 7 non-Soviet. The three most recent references to English-language publications read as follows: J. R. Senitzky. Phys. Rev., 119, 670, 1960; H. J. Mc Connell. J. Chem. Phys., 25, 709, 1956; B. R. Mc Garvey. J. Phys. Chem., 61, 1232, 1957. ASSOCIATION: Kazanskiy pedagogicheskiy institut (Kazan' Pedagogical Institute) Card 7/7 0 (1,6 fply AUTHORS: Timerovo R. Kh., Valiyev, K TITLE: Theoryof nuclear resonance PERIODICAL: Zhurnal eksperimentalinoy i no. 501), 1961, 1566-1575 26708 5/056/61/041/005/023/038 B102/B138 A. in paramagnetic media teoreticheskoy fiziki, v. 41, TEXT: The influence of paramagnetic atoms on nuclear resonance results in the reduction of the relaxation times of the components of nucle 'ar magnetization and in a shift 6 of the nuclear resonance frequency tiI. Where there is low concentration of paramagnetic atoms their effect can be described by an additive law which has been verified theoretically as well as experimentally. In the case of high concentrations, which is that investigated in the present paper, exchange interactiea between para- magnetic ions-,has to be taken into account. This determines the exchange of electron spin orientations reduces the effect of the paramagnetic atoms on relaxation times TH and T.L of the nuclear magnetization components. The authors have developed a theory of the shape and width (T.Cl) Of a Card 1/8 26708 8/056J61/041/005/023/038 Theory.of nuclear resonance in... B102/B138 nuclear resonance line which allows for the exchange interactions between paramagnetic atoms, which are in their turn modulated by the thermal motion in the system. The system contain-i NI magnetic nuclei and ff. paramagnetic atoms per unit volume. The shape of the absorption line IM. is represented as a Fourier transform of the autocorrelation function G(t) of the projection of the magnetic moment in the diroation x of the variable, magnetic field: IM +00 G(t)q- i(4 dt; G(t) (0)J> - In order f Nx -00 to find the parts of the Hamiltonian the first terms of the series G(t) Y-Gn(t) are determined (G,(t). 0): Go (f) NiT211 V + 1) lel'f 1 + K - c. (7) 62 (1) -LN/T2/1 Q + 11[el"t a'~d-r (t - T) e"('f, (T) + x, c], (8) T Card 2/8 267 08 S/056J61/041/005/023/038 Theory of nuclear resonance in ... B102/B138 h-2 1 , with G. + Y 4- Ti (9) R < J A71'+O), AF, (r) (0). MT) J>, it' (T) ~- YJ S'wl% Yf' , (T) I C CXP (iTX-2/h) .7?, exp PrYt,lh). (11) 2 - - ---I M i V-- -- 0 is the contribution fro to the second moment of the resonance line (in frequency units), f (-r) the correlation function of the Yl(-r) values, Y A Y. which vary with time due to the effect of 7C2, and N is R formal operator: NA(t) -A(t)/.A(O)l the prime denotes the perturbation terms, +X C. means: + complex conjugates. Por Go (t) +02(t) a' dc (t -r) e("l +'q'As) T X CL 1. 2 Y. 0 .0 X ex p + K. C., (21) or, approximately, -------- Card 3/8 26708 S10561611041100510231038 Theory of nuclear resonance invas B102/B136 exp li(olt - 0711-2 d-r(t-T)e~("I'"ws X a 1.2 Y.0 0 x exp I --- 71 ~ I v.-' - I c 17-01 - OF (T))1 + K. C. (22) is found; In the expression (21) only a constant factor is omitted.' Then' the line shape is calculated for two limiting cases: fast (fluid) and slow (viscous liquid or solid) motion of the molecules of the system. In the first case, TO ~>Te, from (22) oranother formula the half-width of a Lorentz line with its center at ej + 6 Is found to be S (S + KO-11 + 1)(111S I I S 2 K-12 + to 4 V,, + V + (.s + ;1), 4* 12,jiT, oa/ (0.02 K12' + S (S + 1) K. + )2 (23) 3 T~~Caj - WS The shift (in rad/sec) is determined by Card 4/8 26708 8/056/61/041/005/023/038 Theory of nuclear resonance in... B102/B138 t C.)i + WS 6 = S P + 1) (is ~ 2 K,-12 + w21 + 2 K',, + (w, + + C01 - (OS _WS (24) " I + S (S + 1) KI-2 12 K-1 + ((01 - (OS) 2 + (_I - (OS)l -1 2 (25) T;I + TV + + T, + >1 The reciprocal relaxation times T 1 and T 2 are, for paramagnetic ions of the Cu 2+ 'VO 2+ type, of the order of 108 eec -1 , for others much shorter -1 '* 11 -1 still; -ri -10 sec . Estimations show that very different situations may arise. For large W e the half-width can be approximated by A& S(S+l)F20 2 + L I /Te&)e 71 B(S+1)62 K +j-S(8+1)K For slow thermal motion, (A'JI/2)h-f ' 22 is P'I 3 P,2' TO