th  - 1988 - 51st ENC Conference

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I TUE Eve 7"301MAGNETIC RESONANCE STUDIES OF HIGH TEMPERATURE SUPERCONDUCTORS: Charles P. Slichter, University of Illinois at Champaign-Urbana, Urbana, IL 61801 Nuclear spin-lattice relaxation times give important information about superconductors. The talk will briefly review the reasons. Then, it will turn to Cu NMR and NQR studies of powders of the 40 K superconductor Lal.85Ba.15CuO 4 and NMR studies of single crystals of the 90 K superconductor YBa2Cu307_ 6. Supported through the University of Illinois Materials Research Laboratory by the Department of Energy Division of Materials Research under Contract DE-AC01- 76ERO1198. 44
• . r T[-~-UE ~ t~ve 8:00! 63,65Cu NQR STUDIES OF HIGH T OXIDE SUPERCONDUCTORS: W. W. Warren, Jr.*, R. E. Walstedt, G. F. Brennert, R. F c. Bell, R. J. Cava, G. P. Espinosa, and J. P. Remeika, AT&T Bell Laboratories, Murray Hill, NJ 07974 Nuclear quadrupole resonance provides a local, site selective probe which has proven highly informative for studies of oxide superconductors. In this talk I will review our investigations using the 6~,6SCu resonances in the 90 K superconductor YBa2Cu3OT_8" The crystal structure of YBa2Cu307 contains two inequivalent Cu sites (Cu-O ".chains" and "planes") whose NQR lines fall at roughly 22 MI-Iz and 31.5 MHz. Although electron band theory calculations imply similar electronic structure at the two sites, spin-lattice relaxation time measurements reveal strikingly different behavior in both the normal and superconducting states. In the normal states, the 22 MHz sites relax by an enhanced Korringa process that exhibits the usual roughly linear temperature dependence for the relaxation rate. At 31 MHz, in contrast, the rate increases only slightly with increasing temperature. Below To, spin-lattice relaxation reflects the excitation spectrum of unpaired electrons ("quasiparticles"). Again, the relaxation behavior is dramatically different for the two sites. An exponential representation of the relaxation rate yields a value 2A / kT c -- 2.4 for the 22 MI-Iz sites (A is the superconducting energy gap) while for 31.5 MHz, the corresponding value is 2A / kT c -- 8.3. Reduced oxygen content (8 = 0.3) leads to relaxation at the 31.5 MHz sites reduced by a factor - 1/1500 but only a modest 30 ~o effect at 22 MHz. This indicates that the former sites carry almost no conduction electron density and, by implication, do not participate in the 60 K superconductivity observed in this phase. The effects of extrinsic paramagnetic moments, the assignment of the NQR lines to the respective Cu sites, and the implications of these results of models of superconductivity will be discussed. 45
Page 1 and 2: 29 th �� - 1988 Rochester
Page 3 and 4: PROGRAM: This conference program ha
Page 5 and 6: The Executive Committee of the 29th
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Page 9 and 10: Restaurants in Rochester Restaurant
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Page 15 and 16: f~ I UNTRUNCATIO~I OF DIPOLE-DIPOLE
Page 17 and 18: MON 9:25 HIGH RESOLUTION ELECTROPHO
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Page 21 and 22: ~'-O-i 0 N i0:55 MEASUREMENTS OF TW
Page 23 and 24: MON 11:3S 12D CHEMICAL SHIFT ANISOT
Page 25 and 26: 7:30 p.m. 8:00 p.m. 8:10 p.m. 8:40
Page 27 and 28: HON Eve 8:00 The 13C Relaxation Beh
Page 29 and 30: THE WORLD AND WONDERS OF 3H NMR SPE
Page 31 and 32: 8:30 a.m. 9:00 a.m. 9:10 a.m. 9:20
Page 33 and 34: TWO DIMENSIONAL LINEAR PREDICTION N
Page 35 and 36: TUE 9"20 ] 2D ROTATING FRAME SPECTR
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Page 39 and 40: TUE ii'00 J WATER SUPPRESSION TECHN
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Page 47 and 48: TUE Eve 8-50 } Cu NQR OF YBa2Cu30 x
Page 49 and 50: ~X [I'IED 8:30 I REMOVAL OF EXTRANE
Page 51 and 52: . r WED 9:25 ] A STATIC NMR IMAGE O
Page 53 and 54: WED 9" 45 IFLUID AND SOLID STATE NM
Page 55 and 56: i MULTIVOLUME SELECTIVE SPECTROSCOP
Page 57 and 58: [WED 11-10 I SELF SHIELDED GRADIENT
Page 59 and 60: [WED 11:45 ] ANGIOGRAPHY USING MAGN
Page 61 and 62: THU 8:30 "TETHERED" BIOLOGICAL SYST
Page 63 and 64: • / I DYNAMICS OF THE GRAMICIDIN
Page 65 and 66: I THU 9:40 I NMR STUDIES OF ANTI-SP
Page 67 and 68: THU 10"2S I NEW TECHNIQUES POR DYNA
Page 69 and 70: I THU 11 : 05 I DYNAMIC NUCLEAR POL
Page 71 and 72: THIS SECTION CONTAINS A LISTING OF
Page 73 and 74: 9 ELIMINATION OF PHASE ROLL, SOLVEN
Page 75 and 76: 25 NUCLEAR MAGNETIC RESONANCE STUDI
Page 77 and 78: ~k 41 A HYPO-RELAXATION AGENT; SIMU
Page 79 and 80: 57 STRUCTURAL STUDIES OF LIPIDS IN
Page 81 and 82: 73 THE AUTOMATED NMR LABORATORY; SP
Page 83 and 84: 89 13C NMR ASSIGNMENTS OF DNA OLIGO
Page 85 and 86: 105 EVALUATION OF DOUBLE TUNED CIRC
Page 87 and 88: 121 BROADBAND SPIN DECOUPLING IN TH
Page 89 and 90: 137 TWO-DIMENSIONAL 13C{15N}, 13C{1
Page 91 and 92: 153 NMR CHARACTERIZATION OF THE SOL
Page 93 and 94: 169 SPECTROSCOPY WITH EXACT APODIZA
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185 PARSING THE EDITED 1H NMR SIGNA
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. z 201 THE CORRELATION OF 1H-19F C
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i m 3 I 31p SOLID STATE NMR STUDIES
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CALCULATION OF 2951MAS NMR CHEMICAL
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AN NMR STUDY OF MISCIBLE BLENDS IN
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15 II9F CRAMPS OF INORGANIC FLUORID
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19 I DIPOLARAND SPIN-ROTATION POLAR
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2 3- I A SOLID-STATE 2H and 13C NMR
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27 1 COLLECTION OF PHOSPHORUS-31 NM
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31 DELAYED REFOCUSSING TWO-DIMENSIO
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35 DYNAMIC NUCLEAR POLARIZATION STU
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I 39 2D NMR STUDIES AT 600 MHZ OF A
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43 Coherent Averaging Theory Under
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46 CARBON-13 SPECTRAL ASSIGNMENTS O
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a b 48 SEMUT SPECTRAL EDITING, CALI
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'--- V 5 2 j INTERCONWERSION OF VAL
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[ ~ THE SOURCE OF AN ARTIFACT IN TH
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60 GLUCOSE METABOLISM IN PERFUSED H
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. °- F 64 I MICROSCOPIC IMAGING OF
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68 69 CONFORMATIONAL ANALYSIS via V
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72 I SCUBA, A MAY TOHARDS COMPLETE
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76 NMR CHARACTERIZATION OF THE GLYP
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8o I HIGH RESOLUTION MR IMAGING AT
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A PROBE WITH HIGHER DECOUPLING EFFI
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88 I SOLID STATE ll3cd I~CLEAR }~GE
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- - 92 l CHARACTERIZATION OF NORMAL
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96 AN EVALUATION OF NEW PROCESSING
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. . I00 I NOVEL RESONATOR DESIGNS,
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104 TAYLOR TRANSFORMATION OF 2D NMR
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108 PERFORMANCE COMPARISON OF DOUBL
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RECENT EXTENSIONS OF NOESYSIM, A PR
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116 ] NODIFICATIONS TO A JEOL GX270
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I 12 o I SPECIATION OF WATER IN GLA
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124 I A COMPLETELY INTEGRATED NETWO
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I-- 1 2 8 IVOLUME-SELECTIVE SIGNAL
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-- is 2 I NATURAL ABUNDANCE 13 C an
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. ° THREE-DIMENSIONAL STRUCTURE OF
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~-'-- 140 DIRECT OBSERVATION OF LON
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144 I I IH AND 13C REFOCUSED GRADIE
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~ (POSTER ABSTRACT) BARBARA LYONS/C
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1 52 I ~IR STUDY OF NAPHTHALENE TRA
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is6 I ROTATING FRAME COHERENCE TRAN
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16 0 I A 27AL MAS STUDY OF AMORPHOU
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164 I MODIFICATIOH OF A BRUKER WH-3
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IN VIVO 31p AND IH NMR SPECTROSCOPY
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. r 172 JMAGIC ANGLE SPINNING SEPAR
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2 . ° I- 176 I Michael A. Kennedy
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. o . o 180 l17o/Is NMR MICROSCOPY
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To be presented at the 29th Experim
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INHIBITION OF ALANINE RACEMASE BY T
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192 RESOLUTION ENHANCEMENT OF PHOSP
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196 1 TR FLUOROETHOXY DERIVATIVES:
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200 INTERPRETAT IION OF 13 C NHR MI
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204 RECENT PROGRESS IN HIGH RESOLUT
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Page No. ACEVEDO, H F 165 ACKERMAN,
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1:~ge No. GUO, D 200 GUO, W 196 GUO
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OPELLA, S J ORENDT, A M OTTING, G P
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ZLOTNIK-MAZORIo T ZUMBULYADIS, N Pa
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David B. Bailey USI Chemicals Co. 1
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Yvan Boulanger Univ de Montreal Ins
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Helga Cohen Univ of So Carolina Che
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F. David Doty Doty Scientific Inc.
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Alan Freyer Pennsylvania State Univ
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Gordon Hamer Xerox Research Center-
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Timothy Hyman Syracuse University 3
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Robert A Kinsey BF Goodrich 9921Bre
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Jay J. Listinsky U of Rochester-Dep
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Dale Mierke Univ of Calif, San Dieg
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Jeanne C Owens Chemistry Dept., '.1
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Gade S. Reddy DuPont Experimental S
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Charles Schramm Catalytica Assoc. I
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Richard F. Sprecher U.S. Dept of En
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Steve Unger U. C. Davis NMR Facilit
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Toni Wirthlin Varian Associates 611
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th  - 1988 - 51st ENC Conference

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